Previously, we were trying to install all doc files under "share/doc/rust"
which caused `rust-installer` tool to create backup files (*.old) due to filename
conflicts. With this change, doc files is now installed under "share/doc/{package}",
where {package} could be rustc, cargo, clippy, etc.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

Also replaces an incomplete test

Previously, we used the entire sysroot binary path to prepare rustc tarballs.
Since we also copy tool binaries to the sysroot binary path, installing rustc
and tools with `x install` results in attempting to install the same binaries
more than once. This causes rust-installer to create backup files (*.old) due
to file conflicts. This change fixes that.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

To help remind forgetful people like me what step they forgot.

… r=fmease

make "invalid fragment specifier" translatable

…bertlarsan68

distribute tool documentations and avoid file conflicts on `x install`

I suggest reading commits one-by-one with the descriptions for more context about the changes.

Fixes rust-lang#115213

…=Nadrieril

Extend Level API

I need this API for rust-lang/rust-clippy#12303: I have a nested `cfg` attribute (so a `MetaItem`) and I'd like to still be able to match against all possible kind of `Level`s.

…s, r=dtolnay

Implement `NonZero` traits generically.

Tracking issue: rust-lang#120257

r? `@dtolnay`

…rochenkov

Add help to `hir_analysis_unrecognized_intrinsic_function`

To help remind forgetful people like me what step they forgot.

(If this just ICE'd, rust-lang/compiler-team#620 style, the stack trace would point me here, but since there's a "nice" error that information is lost.)