[llvm] [AArch64][GlobalISel] Fix incorrect codegen for FPR16/FPR8 to GPR copies (PR #171499)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> Has this been backported as a fix to earlier releases? Apologies if that's obvious, I'm not familiar with the process here.

No. If you want to add it to the release, you need to set the release milestone and use /cherry-pick to attempt auto-applying to the branch 

https://github.com/llvm/llvm-project/pull/171499