[llvm] [RISC-V] Fix incorrect epilogue_begin (PR #120623)

[Venkata Ramanaiah Nalamothu via llvm-commits]

RamNalamothu wrote:

> Make a separate PR. The github web interface won't let you push a PR as two separate commits.

#120622 for the interface change.

https://github.com/llvm/llvm-project/pull/120623