fix qwen2 tp16

Author: shihaobai

lightllm/models/llama/layer_infer/transformer_layer_infer.py

@@ -39,8 +39,8 @@ def __init__(self, layer_num, network_config, mode=[]):
         super().__init__(layer_num, network_config, mode)
         self.eps_ = network_config["rms_norm_eps"]
         self.tp_q_head_num_ = network_config["num_attention_heads"] // self.tp_world_size_
-        self.tp_k_head_num_ = network_config["num_key_value_heads"] // self.tp_world_size_
-        self.tp_v_head_num_ = network_config["num_key_value_heads"] // self.tp_world_size_
+        self.tp_k_head_num_ = max(network_config["num_key_value_heads"] // self.tp_world_size_, 1)
+        self.tp_v_head_num_ = max(network_config["num_key_value_heads"] // self.tp_world_size_, 1)
         self.tp_o_head_num_ = self.tp_q_head_num_
         self.head_dim_ = network_config["hidden_size"] // network_config["num_attention_heads"]
         self.embed_dim_ = network_config["hidden_size"]