Fix forward_intermediates() grad_checkpointing in vision_transformer.py

Author: rwightman

timm/models/vision_transformer.py

@@ -827,7 +827,7 @@ def forward_intermediates(
             if attn_mask is not None:
                 x = blk(x, attn_mask=attn_mask)
             elif self.grad_checkpointing and not torch.jit.is_scripting():
-                x = checkpoint(blk. x)
+                x = checkpoint(blk, x)
             else:
                 x = blk(x)
             if i in take_indices: