[llvm] [GISel][RISCV]Implement indirect parameter passing for large scalars (PR #95429)

[Gábor Spaits via llvm-commits]

spaits wrote:

> Could you change in the summary: Currently I put the code in TargetLowering::handleAssignments and I think it is general enough for all the targets to to Currently I put the code in CallLowering::handleAssignments and I think it is general enough for all the targets to

Updated the description. I have also finished that sentence :) .

https://github.com/llvm/llvm-project/pull/95429