[llvm] [RISCV] Don't cost scalar fp ops as more expensive than vector fp ops (PR #99594)

[Philip Reames via llvm-commits]

preames wrote:

I agree that it would be better to increase the vector FP costs than to decrease the scalar costs.  I doubt it'll matter that much overall, but it seems a bit more consistent.  If there's no other reason to prefer one over the other, I'd prefer to see the vector cost increase.

https://github.com/llvm/llvm-project/pull/99594