update the rustc submodule

[oli-obk]

I won't get to it anytime soon. All that's needed is to point the submodule (src/tools/clippy) in the rustc repo to the master branch of this repo and run the x.py script to update the Cargo.lock and open a pr with said changes

[phansch]

Will give this a try today 👍

[phansch]

This would require a new clippy release, no?
I manged to update the submodule, but running cargo update -p clippy makes no changes

[oli-obk]

Should be fine. Releases of submodules make no difference if no dependencies changed. Try running. /x.py without any args (after git add-ing the submodule).