Don't cast dtype right after tensor creation in to_dense_batch

Author: akihironitta

torch_geometric/utils/_to_dense_batch.py

@@ -123,8 +123,8 @@ def to_dense_batch(
         x, idx = x[mask], idx[mask]
 
     size = [batch_size * max_num_nodes] + list(x.size())[1:]
-    out = torch.as_tensor(fill_value, device=x.device)
-    out = out.to(x.dtype).repeat(size)
+    out = torch.as_tensor(fill_value, device=x.device, dtype=x.dtype)
+    out = out.repeat(size)
     out[idx] = x
     out = out.view([batch_size, max_num_nodes] + list(x.size())[1:])