Revert LLVM D81803 because it broke Windows 7

This submodule update reverts <https://reviews.llvm.org/D81803>.

While that change is meant to fix a real bug, [LLVM PR42623], it caused
new permission errors on Windows 7 that make it unable to build any
archives. This is probably the same root cause as [LLVM PR48378].

Fixes #81051. We'll file a new Rust issue to track the LLVM resolution.

[LLVM PR42623]: https://bugs.llvm.org/show_bug.cgi?id=42623
[LLVM PR48378]: https://bugs.llvm.org/show_bug.cgi?id=48378