[lld] [LLD][RISCV] Fix incorrect call relaxation when mixing +c and -c objects (PR #73977)

[Paul Kirth via llvm-commits]

ilovepi wrote:

Thanks for running this down. When I started looking into #65090 I found https://github.com/llvm/llvm-project/issues/63964., but wasn't sure they were related, since we only saw this in LTO builds and we use the C extension everywhere.  

I'm not sure if this patch will be able to resolve the LTO issues we saw, since I don't think the section flags will be relevant in the LTO case, but it's certainly a welcome improvement.

@jrtc27 I assume that https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/393 is the latest incarnation of the idea. Do you think it is likely to be accepted? It seems like a much more robust approach from reading the proposal and comments.

https://github.com/llvm/llvm-project/pull/73977