cmd_usage(): simplify return code handling

Lots of code use this construct:

	cmd_usage(cmdtp);
	return 1;

Change cmd_usage() let it return 1 - then we can replace all these
ocurrances by

	return cmd_usage(cmdtp);

This fixes a few places with incorrect return code handling, too.

Signed-off-by: Wolfgang Denk <wd@denx.de>

common/command.c

@@ -153,7 +153,7 @@ int cmd_usage(cmd_tbl_t *cmdtp)
 	puts (cmdtp->help);
 	putc ('\n');
 #endif	/* CONFIG_SYS_LONGHELP */
-	return 0;
+	return 1;
 }
 
 #ifdef CONFIG_AUTO_COMPLETE