Add device_map config to support chatglm2-6b (#734)

chatglm-6b和chatglm2-6b的参数命名不一致，本次提交旨在解决chatglm2-6b device_map 创建的问题。在chatglm_auto_configure_device_map 函数中新增了chatglm2-6b device_map 创建的相关代码。

models/loader/loader.py

@@ -257,10 +257,21 @@ class LoaderCheckPoint:
         # 在调用chat或者stream_chat时,input_ids会被放到model.device上
         # 如果transformer.word_embeddings.device和model.device不同,则会导致RuntimeError
         # 因此这里将transformer.word_embeddings,transformer.final_layernorm,lm_head都放到第一张卡上
+        
+        encode = ""
+        if 'chatglm2' in self.model_name:
+            device_map = {
+                f"{layer_prefix}.embedding.word_embeddings": 0,
+                f"{layer_prefix}.rotary_pos_emb": 0,
+                f"{layer_prefix}.output_layer": 0,
+                f"{layer_prefix}.encoder.final_layernorm": 0,
+                f"base_model.model.output_layer": 0 
+            }
+            encode = ".encoder"
+        else:
             device_map = {f'{layer_prefix}.word_embeddings': 0,
                       f'{layer_prefix}.final_layernorm': 0, 'lm_head': 0,
                       f'base_model.model.lm_head': 0, }
-
         used = 2
         gpu_target = 0
         for i in range(num_trans_layers):
@@ -268,7 +279,7 @@ class LoaderCheckPoint:
                 gpu_target += 1
                 used = 0
             assert gpu_target < num_gpus
-            device_map[f'{layer_prefix}.layers.{i}'] = gpu_target
+            device_map[f'{layer_prefix}{encode}.layers.{i}'] = gpu_target
             used += 1
 
         return device_map