Revert "Remove outdated build rustdoc --stage 1"
Revert "Remove outdated build rustdoc --stage 1"

This reverts commit cd35d2b5944d8436350b7f2f16f5e720d9912db6.

rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide