[InstrProf][NFC] Remove stray option in InstrProfWriter

[ellis]

Summary

This variable was added to InstrProfWriter.cpp in D115693 by mistake and it isn't needed.

[kyulee]

LGTM

llvm/lib/ProfileData/InstrProfWriter.cpp

 #include <cstdint>
 #include <memory>
 #include <string>
 #include <tuple>
 #include <utility>
 #include <vector>
 
 using namespace llvm;
-extern cl::opt<bool> DebugInfoCorrelate;
 
 // A struct to define how the data stream should be patched. For Indexed
 // profiling, only uint64_t data type is needed.
 struct PatchItem {
   uint64_t Pos; // Where to patch.
   uint64_t *D;  // Pointer to an array of source data.
   int N;        // Number of elements in \c D array.
 };