[llvm] [RISCV] Fix musttail with indirect arguments by forwarding incoming pointers (PR #185094)

[Folkert de Vries via llvm-commits]

folkertdev wrote:

> I could do a follow-up fix for loongarch, but considering I missed the swapped-args case, this might suggest there may be other subtle scenarios I missed...

I tagged the loongarch maintainer because my riscv patch was heavily based on their patch for loongarch. The two backends are fairly similar.

https://github.com/llvm/llvm-project/pull/185094