[llvm] [RISCV] Lower llvm.clear_cache to __riscv_flush_icache for glibc targets (PR #93481)

[via llvm-commits]

dyung wrote:

> @dyung if you can revert the change that'd be helpful, so I can investigate. Thanks!

Oddly it no longer seems to be failing on the bot and I don’t think there was a revert. Perhaps it was some unrelated change? I’ll try to verify today whether it was your change or not that caused the test failures. 

https://github.com/llvm/llvm-project/pull/93481