llpc/dbginfo: remove dead code in transFunction

isDefinition is always true, so createMethod could never be called. It
is also unclear how useful calling createMethod is at this point. It
seems the primary difference to createFunction is supporting vtable info
and this-pointer adjustments, but neither concept seems to exist in
NonSemantic.Shader.DebugInfo.100

llpc/translator/lib/SPIRV/SPIRVToLLVMDbgTran.cpp

@@ -504,12 +504,8 @@ DINode *SPIRVToLLVMDbgTran::transFunction(const SPIRVExtInst *DebugInst) {
   DINodeArray TParams = Builder.getOrCreateArray(Elts);
   llvm::DITemplateParameterArray TParamsArray = TParams.get();
 
-  DISubprogram *DIS = nullptr;
-  if ((isa<DICompositeType>(Scope) || isa<DINamespace>(Scope)) && !IsDefinition)
-    DIS = Builder.createMethod(Scope, Name, LinkageName, File, LineNo, Ty, 0, 0, nullptr, Flags, SPFlags, TParamsArray);
-  else
-    DIS =
-        Builder.createFunction(Scope, Name, LinkageName, File, LineNo, Ty, ScopeLine, Flags, SPFlags, TParamsArray, FD);
+  DISubprogram *DIS =
+      Builder.createFunction(Scope, Name, LinkageName, File, LineNo, Ty, ScopeLine, Flags, SPFlags, TParamsArray, FD);
   DebugInstCache[DebugInst] = DIS;
   SPIRVId RealFuncId = Ops[FunctionIdIdx];
   FuncMap[RealFuncId] = DIS;