[mlir][tensor] Implement folding logic for size 0 tensor and memref ops (#90814)
Implement folding and rewrite logic to eliminate no-op tensor and memref
operations. This handles two specific cases:
1. tensor.insert_slice operations where the size of the inserted slice
is known to be 0.
2. memref.copy operations where either the source or target memrefs are
known to be emtpy.
Co-authored-by: Spenser Bauman <sabauma@fastmail>