[llvm] [RISCV] Add ISel patterns for Qualcomm uC Xqcicm extension (PR #145643)

[Craig Topper via llvm-commits]

topperc wrote:

Will you be adding commuting support for the rd/rs3 sources? That should avoid some copies if rs3 is a better match for the destination register.

https://github.com/llvm/llvm-project/pull/145643