[llvm] [AMDGPU][AsmParser] Eliminate validateExeczVcczOperands(). (PR #102600)

[Ivan Kosarev via llvm-commits]

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@@ -3039,7 +3038,8 @@ bool AMDGPUAsmParser::ParseAMDGPURegister(RegisterKind &RegKind, unsigned &Reg,
     if (Reg == AMDGPU::SGPR_NULL) {
       Error(Loc, "'null' operand is not supported on this GPU");
     } else {
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kosarev wrote:

`MCAsmParser::Error()` seems to return true, so wouldn't work. (Confusingly, our `AMDGPUAsmParser::Error()` returns false, but from what I see that's not what we call here.)

https://github.com/llvm/llvm-project/pull/102600