[llvm] [RISCV][VLOPT] Add fsqrt instruction to isSupportInstr (PR #127462)

[Luke Lau via llvm-commits]

https://github.com/lukel97 commented:

Thanks! Can you also add some LLVM IR tests in vl-opt-instrs.ll?

https://github.com/llvm/llvm-project/pull/127462