[X86] Use int64_t and isInt<N> instead of APInt operations in foldLoadStoreIntoMemOperand. NFC

We know all our values are limited to 64 bits here so we don't need an APInt.

This should save some generated code checking between large and small size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358338 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed