[llvm] [JITLink][RISCV] Implement .eh_frame handling (PR #66067)

[Alex Bradbury via llvm-commits]

asb wrote:

I haven't followed the set of related discussions on this, but just to note the lack of this is currently causing a test failure in the clang-repl tests for RISC-V (seemingly a test case that was enabled by https://reviews.llvm.org/D159167). As the rv64gc qemu-user builder has been stable for a long time (i.e. only flagging actual bugs introduced by patches), I'd like to move it from the staging buildmaster, but would obviously like to see it go green before doing so.

https://github.com/llvm/llvm-project/pull/66067