[MLIR] Add Linalg support for integer (generalized) matmuls

This patch adds Linalg named ops for various types of integer matmuls.
Due to limitations in the tc spec/linalg-ods-gen ops cannot be type
polymorphic, so this instead creates new ops (improvements to the
methods for defining Linalg named ops are underway with a prototype at
https://github.com/stellaraccident/mlir-linalgpy).

To avoid the necessity of directly referencing these many new ops, this
adds additional methods to ContractionOpInterface to allow classifying
types of operations based on their indexing maps.

Reviewed By: nicolasvasilache, mravishankar

Differential Revision: https://reviews.llvm.org/D97006