Update on "[ET-VK][ez] Support exporting of custom operator calls via higher_order_auto_functionalized"

As title. This diff adds the ability to partition custom op calls to the Vulkan delegate.

Differential Revision: [D63913434](https://our.internmc.facebook.com/intern/diff/D63913434/)

[ghstack-poisoned]

Author: SS-JIA

backends/vulkan/partitioner/vulkan_partitioner.py

@@ -121,6 +121,7 @@ def is_in_local_scalar_dense_chain(self, node: torch.fx.Node) -> bool:
         if node.target == exir_ops.edge.aten.select_copy.int:
             if len(node.users) != 1:
                 return False
+            # pyre-ignore
             if node.args[0].meta["val"].numel() != 1:
                 return False