[mlir][sparse] fuse collapse_shape on sparse tensor with GenericOp.

Instead of always materializing a new sparse tensor after reshape, this patch tries to fuses the reshape (currently only on COO) with GenericOp and coiterates with the reshaped tensors without allocating a new sparse tensor.

Reviewed By: aartbik

Differential Revision: https://reviews.llvm.org/D145016