[nfc][sancov] Remove unnecessary default argument (llvm#117464)

Author: vitalybuka

llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp

@@ -244,7 +244,7 @@ class ModuleSanitizerCoverage {
   void InjectTraceForSwitch(Function &F,
                             ArrayRef<Instruction *> SwitchTraceTargets);
   bool InjectCoverage(Function &F, ArrayRef<BasicBlock *> AllBlocks,
-                      bool IsLeafFunc = true);
+                      bool IsLeafFunc);
   GlobalVariable *CreateFunctionLocalArrayInSection(size_t NumElements,
                                                     Function &F, Type *Ty,
                                                     const char *Section);