[llvm] MachineTraceMetrics: always include instr latency in depth (PR #73550)

[Ramkumar Ramachandra via llvm-commits]

artagnon wrote:

> This doesn't seem to be true from my inspection of `getOperandLatency`: in fact, `getOperandLatency` falls back to `getInstrLatency` in some cases, and even in cases when it doesn't, the latency of the instruction is implicitly included in its computation. Please correct me in case I've misunderstood something.

Sorry, it includes the instruction latency of DefMI, not UseMI. I'll have to re-think this patch.

https://github.com/llvm/llvm-project/pull/73550