Standardize command usage messages with cmd_usage()

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/common/cmd_log.c b/common/cmd_log.c
index febdb90..6f8a27f 100644
--- a/common/cmd_log.c
+++ b/common/cmd_log.c
@@ -241,11 +241,11 @@
 			}
 			return 0;
 		}
-		printf ("Usage:\n%s\n", cmdtp->usage);
+		cmd_usage(cmdtp);
 		return 1;
 
 	default:
-		printf ("Usage:\n%s\n", cmdtp->usage);
+		cmd_usage(cmdtp);
 		return 1;
 	}
 }