[clang] [llvm] [RISCV] Support Base P RV32/64 Instructions (PR #150379)

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realqhc wrote:

> I missed this patch in my email. I posted #153458 for the other shift instructions. I used RVPShiftD_ri instead of RVPShiftD_ri. D would be the usual suffix for "doubleword" or 64 bits.

Thanks, I will modify this patch to include p15-17 using your sugessions after #153629 is merged. 

https://github.com/llvm/llvm-project/pull/150379