[llvm] [RISCV][MC] Implement evaluateBranch for auipc+jalr pairs (PR #65480)

[Job Noorman via llvm-commits]

mtvec wrote:

> I think the optimization does make sense unless it makes the code a lot less readable.

I don't think it makes the code unreadable so I implemented the optimization.

https://github.com/llvm/llvm-project/pull/65480