fix FLUX.2 context parallel (#12737)

Author: DefTruth

src/diffusers/models/transformers/transformer_flux2.py

@@ -676,8 +676,8 @@ class Flux2Transformer2DModel(
         "": {
             "hidden_states": ContextParallelInput(split_dim=1, expected_dims=3, split_output=False),
             "encoder_hidden_states": ContextParallelInput(split_dim=1, expected_dims=3, split_output=False),
-            "img_ids": ContextParallelInput(split_dim=0, expected_dims=2, split_output=False),
-            "txt_ids": ContextParallelInput(split_dim=0, expected_dims=2, split_output=False),
+            "img_ids": ContextParallelInput(split_dim=1, expected_dims=3, split_output=False),
+            "txt_ids": ContextParallelInput(split_dim=1, expected_dims=3, split_output=False),
         },
         "proj_out": ContextParallelOutput(gather_dim=1, expected_dims=3),
     }