[mlir][tosa][fix] Add proper type checking trait for tosa mul

when operating integer type tensors, tosa elementwise multiplication
requires the element type of result to be a 32-bit integer rather
than the same type as inputs.

Change-Id: Ifd3d7ebd879be5c6b2c8e23aa6d7ef41f39c6d41

Reviewed By: mgehre-amd

Differential Revision: https://reviews.llvm.org/D154988