Fix LatteTransformer3DModel dtype mismatch with enable_temporal_attentions (huggingface#11139)

Author: hlky

src/diffusers/models/transformers/latte_transformer_3d.py

@@ -273,7 +273,7 @@ def forward(
                 hidden_states = hidden_states.reshape(-1, hidden_states.shape[-2], hidden_states.shape[-1])
 
                 if i == 0 and num_frame > 1:
-                    hidden_states = hidden_states + self.temp_pos_embed
+                    hidden_states = hidden_states + self.temp_pos_embed.to(hidden_states.dtype)
 
                 if torch.is_grad_enabled() and self.gradient_checkpointing:
                     hidden_states = self._gradient_checkpointing_func(