scripts: mkhash show -n option in usage

The -n option prints the filename of hashed files next to the calculated
checksum. Reflect that in the usage message.

user@dawn:~/src/openwrt/openwrt$ ./a.out md5 -n .config
eb06db36e7b6751cb18801945e46bf5d .config

Signed-off-by: Paul Spooren <mail@aparcar.org>

scripts/mkhash.c

@@ -736,7 +736,10 @@ static int usage(const char *progname)
 {
 	int i;
 
-	fprintf(stderr, "Usage: %s <hash type> [<file>...]\n"
+	fprintf(stderr, "Usage: %s <hash type> [options] [<file>...]\n"
+		"Options:\n"
+		"	-n		Print filename(s)\n"
+		"\n"
 		"Supported hash types:", progname);
 
 	for (i = 0; i < ARRAY_SIZE(types); i++)