[llvm] [RISCV] Enable early if-conversion (PR #92959)

[Pengcheng Wang via llvm-commits]

wangpc-pp wrote:

> @wangpc-pp Thanks for the test case, I'll look into that. I have only tested on x264 train workload and I got 1% impovement in cycle count. Can you share your results?

I haven't run any particular benchmark and I just evaluated it on some internel microbenches. We can see some cycles reduction.

https://github.com/llvm/llvm-project/pull/92959