[llvm] [TableGen] Remove unnecessary use of utostr when writing to raw_ostream. NFC (PR #154800)

[Rahul Joshi via llvm-commits]

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@@ -154,9 +154,9 @@ bool CodeEmitterGen::addCodeToMergeInOperand(const Record *R,
     raw_string_ostream CaseOS(Case);
     CaseOS << indent(6);
     if (UseAPInt) {
-      CaseOS << EncoderMethodName << "(MI, " + utostr(OpIdx) << ", op";
+      CaseOS << EncoderMethodName << "(MI, " << OpIdx << ", op";
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jurahul wrote:

nit: can you also remove the {} around the single-statement if-else?

https://github.com/llvm/llvm-project/pull/154800