[clang] [llvm] [RISCV] Add Zicfiss support to the shadow call stack implementation. (PR #68075)

[Paul Kirth via cfe-commits]

https://github.com/ilovepi approved this pull request.

LGTM. Seems like all of my comments have been addressed. Thanks for the hard work!

https://github.com/llvm/llvm-project/pull/68075