Add patch_mixtral_replace_moe_impl for full training Mitral using DeepSpeed Zero3.

Signed-off-by: ldwang <ftgreat@gmail.com>

src/llmtuner/model/patcher.py

@@ -269,6 +269,7 @@ def patch_config(
 
 
 def patch_mixtral_replace_moe_impl() -> None:
+    import torch.nn.functional as F
     def mlp_forward(self, hidden_states):
         current_hidden_states = self.act_fn(self.w1(hidden_states)) * self.w3(hidden_states)
         current_hidden_states = self.w2(current_hidden_states)