[mlir][spirv] Enable composite instructions for cooperative matrix type.

Enable inset/extract/construct composite ops as well as access chain for
cooperative matrix. ConstantComposite requires more change and will be done in
a separate patch. Also fix the getNumElements function for coopMatrix per
feedback from Jeff Bolz. The number of element is implementation dependent so
it cannot be known at compile time.

Differential Revision: https://reviews.llvm.org/D80321