[IR] Refactor attribute methods in Function class (NFC)

Rename the functions that query the optimization kind attributes.

Differential revision: https://reviews.llvm.org/D60287

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357731 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/SafeStack.cpp

@@ -728,7 +728,7 @@ void SafeStack::TryInlinePointerAddress() {
   if (!isa<CallInst>(UnsafeStackPtr))
     return;
 
-  if(F.optForNone())
+  if(F.hasOptNone())
     return;
 
   CallSite CS(UnsafeStackPtr);