[llvm] [RISCV][MCA] Pick the correct VPseudo sched class for indexed memory operation (PR #128978)

[Min-Yih Hsu via llvm-commits]

mshockwave wrote:

> LGTM and please rebase after @topperc's commits.

Thanks for the heads up, I just rebased and removed the redundant *_IMPL to use the implementations in RISCVBaseInfo.cpp

https://github.com/llvm/llvm-project/pull/128978