[llvm] [RISCV] Match strided load via DAG combine (PR #66800)

[Luke Lau via llvm-commits]

https://github.com/lukel97 approved this pull request.

LGTM. I presume we don't need to worry about scalable vectors if we don't handle them in #66694

https://github.com/llvm/llvm-project/pull/66800