[llvm] [RISCV][VLOPT] Add support for integer multiply-add instructions (PR #112216)

[Craig Topper via llvm-commits]

topperc wrote:

> Should we have tests where vmacc is the using instruction so we test the operand info for the source operands?

Oh I guess we have one test `vmacc_vv_use`. But that only tests one of the source operands.

https://github.com/llvm/llvm-project/pull/112216