[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/Analysis/LoopPass.cpp

@@ -396,7 +396,7 @@ bool LoopPass::skipLoop(const Loop *L) const {
   if (Gate.isEnabled() && !Gate.shouldRunPass(this, getDescription(*L)))
     return true;
   // Check for the OptimizeNone attribute.
-  if (F->optForNone()) {
+  if (F->hasOptNone()) {
     // FIXME: Report this to dbgs() only once per function.
     LLVM_DEBUG(dbgs() << "Skipping pass '" << getPassName() << "' in function "
                       << F->getName() << "\n");