[MLIR][LLVM] Add inline_hint as a first class function attribute (#163324)
We have `noinline` and `alwaysinline` present as first class function
attributes. Add `inline_hint` to the list of function attributes as
well.
Update the module import and translation to support the new attribute.
The verifier does not need to be changed as `inlinehint` does not
conflict with `noinline` or `alwaysinline`.
`inline_hint` is needed to support the `inline` C/C++ keyword in CIR.