[llvm] RISCVAsmParser: Don't treat operands with relocation specifier as parse-time constants (PR #133377)

[Sam Elliott via llvm-commits]

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

LGTM. You may get a large merge conflict with craig's patch to cleanup a lot of the immediate predicates. 

https://github.com/llvm/llvm-project/pull/133377