[mlir][arith] Add overflow flags support to arith ops (#77211)

Add overflow flags support to the following ops:
* `arith.addi`
* `arith.subi`
* `arith.muli`

Example of new syntax:
```
%res = arith.addi %arg1, %arg2 overflow<nsw> : i64
```
Similar to existing LLVM dialect syntax
```
%res = llvm.add %arg1, %arg2 overflow<nsw> : i64
``` 

Tablegen canonicalization patterns updated to always drop flags, proper
support with tests will be added later.

Updated LLVMIR translation as part of this commit as it currenly written
in a way that it will crash when new attributes added to arith ops
otherwise.

Discussion
https://discourse.llvm.org/t/rfc-integer-overflow-flags-support-in-arith-dialect/76025

---------

Co-authored-by: Yi Wu <yi.wu2@arm.com>

0 files changed, 0 insertions, 0 deletions