[llvm] [RISCV] Add QingKe "XW" compressed opcode extension (PR #97925)

[via llvm-commits]

ArcaneNibble wrote:

fwiw the test failure that is showing in CI appears to be spurious (`FAIL: BOLT :: X86/reader-stale-yaml-std.test`)

https://github.com/llvm/llvm-project/pull/97925