Inliner: Don't mark notail calls with the 'tail' attribute

enum TailCallKind { TCK_None = 0, TCK_Tail = 1, TCK_MustTail = 2,
                    TCK_NoTail = 3 };

TCK_NoTail is greater than TCK_Tail so taking the min does not do the
correct thing.

rdar://35639547

llvm-svn: 319075