[llvm] [Xtensa] Implement Xtensa Floating Point Option. (PR #136086)

[Matt Arsenault via llvm-commits]

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@@ -113,6 +113,44 @@ static DecodeStatus DecodeMR23RegisterClass(MCInst &Inst, uint64_t RegNo,
   return MCDisassembler::Success;
 }
 
+static const unsigned FPRDecoderTable[] = {
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arsenm wrote:

```suggestion
static const MCPhysReg FPRDecoderTable[] = {
```

https://github.com/llvm/llvm-project/pull/136086