[TOSA] Add legalization for empty, scatter, slice_scatter, diag_embed (llvm#3792)

- Add Torch to TOSA legalization for the following ops:
  + aten.empty.memory_format
  + aten.scatter.src
  + aten.slice_scatter
  + aten.diag_embed
- Update xfail_sets.py with new e2e results
- Update basic.mlir with new LIT tests


Change-Id: I817ecf207bcfcf97ca54f30c10c76c4f0f4145ae

Signed-off-by: Justin Ngo <[email protected]>

Author: justin-ngo-arm