[llvm] [X86] Use BMM for bitreverse without GFNI (PR #209223)

[Simon Pilgrim via llvm-commits]

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RKSimon wrote:

Add a +gfni,+avx512bmm variant as well to ensure we use bitrev:
```
; RUN: llc < %s -mtriple=x86_64-unknown -mattr=+avx512bw,+avx512vl,+gfni,+avx512bmm | FileCheck %s --check-prefixes=CHECK,BMM
```

https://github.com/llvm/llvm-project/pull/209223