[lldb] [llvm] [AArch64][llvm] Tighten SYSP parsing; don't disassemble invalid encodings (PR #182410)

[via llvm-commits]

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@@ -6317,6 +6318,12 @@ bool AArch64AsmParser::showMatchError(SMLoc Loc, unsigned ErrCode,
     return Error(Loc, "immediate must be an integer in range [1, 64].");
   case Match_InvalidImmM1_62:
     return Error(Loc, "immediate must be an integer in range [-1, 62].");
+  case Match_InvalidSysCR0_7:
+    return Error(Loc, "expected cM operand where 0 <= M <= 7");
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Lukacma wrote:

```suggestion
    return Error(Loc, "expected cM operand where 0 <= N <= 7");
```
Probably better to be consistent here

https://github.com/llvm/llvm-project/pull/182410