Module::getOrInsertFunction: set debug info format (#82505)

Function::Function's constructor sets the debug info format based on the
passed in parent Module, so by using this rather than modifying the
function list directly, we pick up the debug info format automatically.

Author: hvdijk

llvm/lib/IR/Module.cpp

@@ -149,10 +149,9 @@ FunctionCallee Module::getOrInsertFunction(StringRef Name, FunctionType *Ty,
   if (!F) {
     // Nope, add it
     Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage,
-                                     DL.getProgramAddressSpace(), Name);
+                                     DL.getProgramAddressSpace(), Name, this);
     if (!New->isIntrinsic())       // Intrinsics get attrs set on construction
       New->setAttributes(AttributeList);
-    FunctionList.push_back(New);
     return {Ty, New}; // Return the new prototype.
   }