[llvm] Let M68kMCCodeEmitter set Scratch size. (PR #69898)

[Min-Yih Hsu via llvm-commits]

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@@ -505,7 +506,16 @@ std::string VarLenCodeEmitterGen::getInstructionCaseForEncoding(
   if (!PostEmitter.empty())
     SS.indent(I) << "Inst = " << PostEmitter << "(MI, Inst, STI);\n";
 
-  return Case;
+  // Resize the scratch buffer if it's to small.
+  std::string ScratchResizeStr = "";
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mshockwave wrote:

nit: the default ctor of `std::string` already gives you an empty string.

https://github.com/llvm/llvm-project/pull/69898