Refactor: Simplify boolean conditional return statements in lib/Linker

[LegalizeAdulthood]

Summary

Use clang-tidy to simplify boolean conditional return statements

[craig.topper]

lib/Linker/LinkModules.cpp

1644

Use ==

[LegalizeAdulthood]

lib/Linker/LinkModules.cpp

1644

FIxed.

[LegalizeAdulthood]

Update from comments

lib/Linker/LinkModules.cpp

 static bool isLessConstraining(GlobalValue::VisibilityTypes a,
                                GlobalValue::VisibilityTypes b) {
   if (a == GlobalValue::HiddenVisibility)
     return false;
   if (b == GlobalValue::HiddenVisibility)
     return true;
   if (a == GlobalValue::ProtectedVisibility)
     return false;
-  if (b == GlobalValue::ProtectedVisibility)
-    return true;
-  return false;
+  return b == GlobalValue::ProtectedVisibility;
 }
 
 /// Loop through the global variables in the src module and merge them into the
 /// dest module.
 static GlobalVariable *copyGlobalVariableProto(TypeMapTy &TypeMap, Module &DstM,
                                                const GlobalVariable *SGVar) {
   // No linking to be performed or linking from the source: simply create an
   // identical version of the symbol over in the dest module... the
Linker::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P)
     : ETypes(E), IsPacked(P) {}
 
 Linker::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST)
     : ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
 
 bool Linker::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const {
   if (IsPacked != That.IsPacked)
     return false;
-  if (ETypes != That.ETypes)
-    return false;
-  return true;
+  return !(ETypes != That.ETypes);
 }
 
 bool Linker::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const {
   return !this->operator==(That);
 }
 
 StructType *Linker::StructTypeKeyInfo::getEmptyKey() {
   return DenseMapInfo<StructType *>::getEmptyKey();