another meshgrid fix for old pytorch

Summary: Try to fix circleci again.

Reviewed By: nikhilaravi

Differential Revision: D34752188

fbshipit-source-id: 5966c585b61d77df1d8dd97c24383cf74dfb1fae

Author: bottler

pytorch3d/common/compat.py

@@ -66,7 +66,10 @@ def meshgrid_ij(
     """
     Like torch.meshgrid was before PyTorch 1.10.0, i.e. with indexing set to ij
     """
-    if "indexing" in torch.meshgrid.__kwdefaults__:
+    if (
+        torch.meshgrid.__kwdefaults__ is not None
+        and "indexing" in torch.meshgrid.__kwdefaults__
+    ):
         # PyTorch >= 1.10.0
         return torch.meshgrid(*A, indexing="ij")
     return torch.meshgrid(*A)