[llvm] Fix unused-variable in SPIRVBuiltins (PR #200842)

[Dmitry Sidorov via llvm-commits]

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@@ -2968,10 +2968,12 @@ static bool buildEnqueueKernel(const SPIRV::IncomingCall *Call,
   const unsigned LocalSizeElemPtrIdx =
       HasVarArgs ? (BaseArgIdx + 6 + (HasEvents ? 3 : 0)) : IncorrectIdx;
 
-  const unsigned LastArgIdx =
-      (BaseArgIdx + 4 + (HasEvents ? 3 : 0) + (HasVarArgs ? 2 : 0));
-  assert(LastArgIdx < NumArgs && "Incorrect number arguments");
+  assert((BaseArgIdx + 4 + (HasEvents ? 3 : 0) +
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MrSidims wrote:

It's a common practice to just put `[[maybe_unused]]` attribute to such variables. 

https://github.com/llvm/llvm-project/pull/200842