wipefs: fail if more device arguments specified

Currently wipefs process only first device argument and silently ignores
remaining.  Print error instead because it can be quite confusing.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

misc-utils/wipefs.c

@@ -384,6 +384,9 @@ main(int argc, char **argv)
 
 	fname = argv[optind++];
 
+	if (optind != argc)
+		errx(EXIT_FAILURE, _("only one device as argument is currently supported."));
+
 	wp = read_offsets(wp, fname, all);
 
 	if (wp) {