[InstSimplify] Extend icmp-of-add simplification to sle/sgt/sge (#168900)

When comparing additions with the same base where one has `nsw`, the
following simplification can be performed:

```llvm
icmp slt/sgt/sle/sge (x + C1), (x +nsw C2)
=>
icmp slt/sgt/sle/sge C1, C2
```

Previously this was only done for `slt`. This patch extends it to the
`sgt`, `sle`, and `sge` predicates when either of the conditions hold:
- `C1 <= C2 && C1 >= 0`, or
- `C2 <= C1 && C1 <= 0`

This patch also handles the `C1 == C2` case, which was previously
excluded.

Proof: https://alive2.llvm.org/ce/z/LtmY4f

0 files changed, 0 insertions, 0 deletions