[clang] [lld] [llvm] [AArch64] Fix stale +zcm target feature to +zcm-gpr64 (PR #146260)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

The llvm test look OK if you wanted to push those separately.

https://github.com/llvm/llvm-project/pull/146260