[llvm] [RISCV] Add missing hasPostISelHook = 1 to vector pseudos that might read FRM. (PR #114186)

[Craig Topper via llvm-commits]

topperc wrote:

> I don't know if I understand correctly, we don't add `frm` operand for some cases before?

That's correct. I think InsertReadWriteCSR would add it in the tests I looked at, but that pass really isn't supposed to anything for DYN instructions.

https://github.com/llvm/llvm-project/pull/114186