[llvm] MCExpr-ify amd_kernel_code_t (PR #91587)

[Matt Arsenault via llvm-commits]

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@@ -205,8 +205,9 @@ void AMDGPUAsmPrinter::emitFunctionBodyStart() {
   if (STM.isMesaKernel(F) &&
       (F.getCallingConv() == CallingConv::AMDGPU_KERNEL ||
        F.getCallingConv() == CallingConv::SPIR_KERNEL)) {
-    amd_kernel_code_t KernelCode;
+    MCKernelCodeT KernelCode;
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arsenm wrote:

Should keep the AMD prefix/infix here 

https://github.com/llvm/llvm-project/pull/91587