[AArch64] MachineCombiner msub matching

Pattern should be sorted in priority order since the pattern evalutor
stops checking as soon as it finds a faster sequence.
so for a * b - c * d, we prefer to match the 2nd operands of sub,
which can be use msub to fold them.

Refer to https://www.slideshare.net/chimerawang/instruction-combine-in-llvm

Fix https://github.com/llvm/llvm-project/issues/84152