[torchdynamo] Add default decomposition for ops in the dynamo backend

Signed-Off By: Vivek Khandelwal <vivek@nod-labs.com>

python/torch_mlir/dynamo.py

@@ -52,6 +52,15 @@ def _get_decomposition_table():
         aten.native_group_norm,
         aten.split.Tensor,
         aten.split_with_sizes,
+        aten.norm.ScalarOpt_dim,
+        aten.embedding_dense_backward,
+        aten.native_layer_norm_backward,
+        aten.slice_backward,
+        aten.select_backward,
+        aten.upsample_bilinear2d.vec,
+        aten.mse_loss_backward,
+        aten.native_group_norm_backward,
+        aten.sigmoid_backward,
     ])