This PR adds a `build()` constructor for `ConstantIntOp` that takes in
an `APInt`.
Creating an `arith` constant value with an `APInt` currently requires a
structure like the following:
```c
b.create<arith::ConstantOp>(IntegerAttr::get(apintValue, 5));
```
In comparison, the`ConstantFloatOp` already has an `APFloat` constructor
which allows for the following:
```c
b.create<arith::ConstantFloatOp>(floatType, apfloatValue);
```
Thus, intuitively, it makes sense that a similar `ConstantIntOp`
constructor is made for `APInts` like so:
```c
b.create<arith::ConstantIntOp>(intType, apintValue);
```
Depends on https://github.com/llvm/llvm-project/pull/144636
5ed852f7f7