Replace the "NoFramePointerElimNonLeaf" target option with a function attribute.

Replace the "NoFramePointerElimNonLeaf" target option with a function attribute.

There's no need to specify a flag to omit frame pointer elimination on non-leaf
nodes...(Honestly, I can't parse that option out.) Use the function attribute
stuff instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187093 91177308-0d34-0410-b5e6-96231b3b80d8