[PATCH v5 13/18] riscv: Add RVV strlen for multiarch and non-multiarch

[Zihong Yao]

Yes, that's on purpose.

The included string/strlen.c does not emit libc_hidden_builtin_def (strlen) here
once STRLEN is defined, so the explicit no-op redefine is not needed. I left it
out to keep the change minimal.

Zihong