protobuf: cleanup

[ericLemanissier]

remove dead code and patches

identified in #21163 and #21146

Specify library name and version: protobuf/*

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• I've read the contributing guidelines.
• I've used a recent Conan client version close to the currently deployed.
• I've tried at least one configuration locally with the conan-center hook activated.

[github-actions]

🤖 Beep Boop! This pull request is making changes to 'recipes/protobuf//'.

👋 @Hopobcn you might be interested. 😉

[ghost]

I detected other pull requests that are modifying protobuf/all recipe:

• Adding protobuf/3.5.1 #20627
• protobuf: improve discovery of protoc executable in build context #20089
• Fixed issue #18927 #18929
• protobuf: add version 4.23.1 #16098

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[ericLemanissier]

The build is now finished. You can take a look at the results here

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 3 (ce2383fa733fcf127db3e81377ddad10c361dcfe):

• protobuf/3.21.9:
  All packages built successfully! (All logs)

• protobuf/3.21.12:
  All packages built successfully! (All logs)

• protobuf/3.20.0:
  All packages built successfully! (All logs)

• protobuf/3.21.4:
  All packages built successfully! (All logs)

• protobuf/3.19.6:
  All packages built successfully! (All logs)

• protobuf/3.18.1:
  All packages built successfully! (All logs)

• protobuf/3.17.1:
  All packages built successfully! (All logs)

• protobuf/3.19.4:
  All packages built successfully! (All logs)

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Conan v2 pipeline ✔️

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 3 (ce2383fa733fcf127db3e81377ddad10c361dcfe):

• protobuf/3.21.12:
  All packages built successfully! (All logs)

• protobuf/3.21.9:
  All packages built successfully! (All logs)

• protobuf/3.21.4:
  All packages built successfully! (All logs)

• protobuf/3.20.0:
  All packages built successfully! (All logs)

• protobuf/3.19.6:
  All packages built successfully! (All logs)

• protobuf/3.19.4:
  All packages built successfully! (All logs)

• protobuf/3.18.1:
  All packages built successfully! (All logs)

• protobuf/3.17.1:
  All packages built successfully! (All logs)