[mlir][tosa] Resubmit add tosa.conv2d as tosa.fully_connected canonicalization

Fixed the tosa.conv2d to tosa.fully_connected canonicalization for incorrect
output channels. Included uptes to tests to include checks for the result
shapes during canonicalization.

This allows conv2d to transform to the simpler fully_connected operation.

Reviewed By: mravishankar

Differential Revision: https://reviews.llvm.org/D115170