Auto merge of rust-lang#112235 - Kobzol:opt-dist, r=Mark-Simulacrum

Port PGO/LTO/BOLT optimized build pipeline to Rust

This PR ports the `stage-build.py` PGO/LTO/BOLT optimization script from Python to Rust, to make it easier to use dependencies, and make it a bit more robust. The PR switches both the Linux and Windows dist runners to the Rust script and removes the old Python script.

Funnily enough, the Rust port has less lines of code than the Python script :) I think that clearly shows that the Python script really lacked dependencies.

Author: bors

.github/workflows/ci.yml

@@ -408,7 +408,7 @@ jobs:
           - name: dist-x86_64-msvc
             env:
               RUST_CONFIGURE_ARGS: "--build=x86_64-pc-windows-msvc --host=x86_64-pc-windows-msvc --target=x86_64-pc-windows-msvc --enable-full-tools --enable-profiler"
-              SCRIPT: PGO_HOST=x86_64-pc-windows-msvc python src/ci/stage-build.py python x.py dist bootstrap --include-default-paths
+              SCRIPT: python x.py build --set rust.debug=true opt-dist && PGO_HOST=x86_64-pc-windows-msvc ./build/x86_64-pc-windows-msvc/stage0-tools-bin/opt-dist python x.py dist bootstrap --include-default-paths
               DIST_REQUIRE_ALL_TOOLS: 1
             os: windows-2019-8core-32gb
           - name: dist-i686-msvc