[llvm] [RISCV] Use TableGen-based macro fusion (PR #72224)

[Wang Pengcheng via llvm-commits]

wangpc-pp wrote:

@preames
The pathset of TableGen-based macro fusion contains:
* https://github.com/llvm/llvm-project/pull/72219
* https://github.com/llvm/llvm-project/pull/72222
* https://github.com/llvm/llvm-project/pull/73115
* https://github.com/llvm/llvm-project/pull/72224 (this one)
Many thanks for helping review these patches!

https://github.com/llvm/llvm-project/pull/72224