Standardize command usage messages with cmd_usage()

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/board/pcs440ep/pcs440ep.c b/board/pcs440ep/pcs440ep.c
index 73a7a08..01ceece 100644
--- a/board/pcs440ep/pcs440ep.c
+++ b/board/pcs440ep/pcs440ep.c
@@ -780,7 +780,7 @@
 
 	if (argc < 2) {
   usage:
-		printf ("Usage:\n%s\n", cmdtp->usage);
+		cmd_usage(cmdtp);
 		return 1;
 	}