Introduce default-members to the workspace root

[s0me0ne-unkn0wn]

Issue: #1418

This PR aims only to build the Polkadot node software by default when cargo build is run from the repo root, avoiding building tons of packages not necessary to build and run the node.

Must be followed up with proper documentation changes (see #1372 for example; other use cases must be described, too).

[mrcnski]

This is totally random and probably the wrong place to ask it, but are the workers inheriting the profile values correctly? I just build them with the production profile but list-syscalls.rb doesn't work (it did before binary separation). I'm guessing the profile is not applied, particularly lto = true.

[s0me0ne-unkn0wn]

@mrcnski I've caught some output from cargo build --release --verbose and formatted it so it's easy to compare just scrolling the lines, it's polkadot binary and one of the workers. I see no mentions of -C lto here, so chances are it's not propagated properly.

     Running `/home/s0me0ne/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc --crate-name polkadot                --edition=2021 polkadot/src/main.rs               --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=316 --crate-type bin --emit=dep-info,link -C opt-level=3 -C embed-bitcode=no -C metadata=57b404de214ca524 -C extra-filename=-57b404de214ca524 --out-dir /home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps -L dependency=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps --extern color_eyre=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libcolor_eyre-f93ed37c7757fb41.rlib --extern polkadot_cli=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_cli.rlib --extern polkadot_node_core_pvf=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf-4527c8ad49d0dbb8.rlib --extern polkadot_node_core_pvf_common=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_common-c81b0c7912854902.rlib --extern polkadot_node_core_pvf_execute_worker=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_execute_worker-1f84d1b1c9059842.rlib --extern polkadot_node_core_pvf_prepare_worker=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_prepare_worker-ca5fa595684db984.rlib --extern polkadot_overseer=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_overseer-6a7b44e9bf2d1f86.rlib --extern tikv_jemallocator=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libtikv_jemallocator-d9ac9cb80955f730.rlib -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/secp256k1-sys-246fe31b64b3f8a4/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/psm-e3ae4e50088c06e9/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/zstd-sys-7f24cdb9fc33d6f9/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/wasmtime-runtime-4769ec7f9d73c093/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/blake3-c34f860f630619ad/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/blake3-c34f860f630619ad/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/librocksdb-sys-36eae9a495fe1557/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/librocksdb-sys-36eae9a495fe1557/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/tikv-jemalloc-sys-c02e2a4d456b1802/out/build/lib -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/lz4-sys-a151bbd581a19649/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/ring-18e6a20cc221ff7e/out`
     Running `/home/s0me0ne/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc --crate-name polkadot_execute_worker --edition=2021 polkadot/src/bin/execute-worker.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=316 --crate-type bin --emit=dep-info,link -C opt-level=3 -C embed-bitcode=no -C metadata=c78b1ea328e9720f -C extra-filename=-c78b1ea328e9720f --out-dir /home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps -L dependency=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps --extern color_eyre=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libcolor_eyre-f93ed37c7757fb41.rlib --extern polkadot_cli=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_cli.rlib --extern polkadot_node_core_pvf=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf-4527c8ad49d0dbb8.rlib --extern polkadot_node_core_pvf_common=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_common-c81b0c7912854902.rlib --extern polkadot_node_core_pvf_execute_worker=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_execute_worker-1f84d1b1c9059842.rlib --extern polkadot_node_core_pvf_prepare_worker=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_node_core_pvf_prepare_worker-ca5fa595684db984.rlib --extern polkadot_overseer=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libpolkadot_overseer-6a7b44e9bf2d1f86.rlib --extern tikv_jemallocator=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/deps/libtikv_jemallocator-d9ac9cb80955f730.rlib -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/secp256k1-sys-246fe31b64b3f8a4/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/psm-e3ae4e50088c06e9/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/zstd-sys-7f24cdb9fc33d6f9/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/wasmtime-runtime-4769ec7f9d73c093/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/blake3-c34f860f630619ad/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/blake3-c34f860f630619ad/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/librocksdb-sys-36eae9a495fe1557/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/librocksdb-sys-36eae9a495fe1557/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/tikv-jemalloc-sys-c02e2a4d456b1802/out/build/lib -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/lz4-sys-a151bbd581a19649/out -L native=/home/s0me0ne/wrk/parity/polkadot-sdk/target/release/build/ring-18e6a20cc221ff7e/out`

[mrcnski]

Nice!

About my issue, looks like -C lto is getting propogated for --profile production.