[llvm-branch-commits] [SPARC] Promote i32 CTTZ when we have VIS3 (PR #135894)

[via llvm-branch-commits]

https://github.com/koachan created https://github.com/llvm/llvm-project/pull/135894

CTTZ can be implemented in terms of CTLZ, for which there's a native
instruction in VIS3.
Promote i32 CTTZ in that case so that the native instruction gets used.