[llvm] [AMDGPU] Improve s_delay_alu insertion for instructions with multiple defs (PR #210762)

[Madhur Kumar via llvm-commits]

MadhurKumar004 wrote:

>For example, inside emitDelayAlu() where we keep track of LastDelayAlu and calculate skip.

But wont it fail for cases like:
```
VOPD1 (defs r0,r1)
VOPD2 (defs r2,r3)
use r0   // delay(VOPD1)
use r2   // delay(VOPD2)
use r1
```

https://github.com/llvm/llvm-project/pull/210762