[lld] [llvm] [ICF] Add a NOP after branch in ICF thunk to improve debugability (PR #154986)

[Peter Rong via llvm-commits]

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@@ -1913,7 +1913,6 @@ void AsmPrinter::emitFunctionBody() {
 
   // Print out code for the function.
   bool HasAnyRealCode = false;
-  int NumInstsInFunction = 0;
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DataCorrupted wrote:

`NumInstsInFunction` was already calculated for debugging purposes. We just promote them as a class member to help us determine if `DW_AT_LLVM_stmt_sequence` should be emitted.

https://github.com/llvm/llvm-project/pull/154986