[PATCH v2 1/4] riscv: Add multiarch scaffolding for str*/mem* routines

[Yao Zihong]

Just to give a quick update on my side.

I’ve aligned my local branch with the other ongoing RVV submissions and adjusted
it so the RVV path works even with --disable-multi-arch. The layout follows the
existing RISC-V rvf/rvd extension structure and powerpc-style layering, so it
should integrate cleanly with both single- and multiarch builds.

This work is based on your memset patch, with some adjustments on the layering.
Once memset finishes testing cleanly, would you prefer that I start a new thread
for that series, or follow up here?

Thanks,
Zihong