Missed clip-mode arg for repo train script

Author: rwightman

train.py

@@ -116,7 +116,8 @@
                     help='weight decay (default: 0.0001)')
 parser.add_argument('--clip-grad', type=float, default=None, metavar='NORM',
                     help='Clip gradient norm (default: None, no clipping)')
-
+parser.add_argument('--clip-mode', type=str, default='norm',
+                    help='Gradient clipping mode. One of ("norm", "value", "agc")')
 
 
 # Learning rate schedule parameters