[llvm] [RISCV] Enable rematerialization for scalar loads (PR #166774)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

I think that test has been flaky since it landed in tree. There are certainly flakes going back before this PR landed. It's on my TODO list to fix, but haven't gotten to it yet.

https://github.com/llvm/llvm-project/pull/166774