[Arch64][SelectionDAG] Add target-specific implementation of srem

X%C to the equivalent of X-X/C*C is not always fastest path if there is no SDIV pair exist. So check target have faster for srem only first. Add AArch64 faster path for SREM only pow2 case.

Fix https://github.com/llvm/llvm-project/issues/54649

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D122968