parse-options: make OPT_INTEGER's argh explicit

OPTION_INTEGER hardcodes its argh member to be "n", but the decision is
hidden deep in usage_with_options_internal(). Make "n" the default argh
for the OPT_INTEGER macro while leaving it undecided for the OPTION_INTEGER
enum.

This makes it less surprising to users that argh is "n" when using the
OPT_INTEGER macro.

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Reviewed-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin-tag.c b/builtin-tag.c
index dc3db62..080e04a 100644
--- a/builtin-tag.c
+++ b/builtin-tag.c
@@ -376,8 +376,8 @@
 	struct commit_list *with_commit = NULL;
 	struct option options[] = {
 		OPT_BOOLEAN('l', NULL, &list, "list tag names"),
-		{ OPTION_INTEGER, 'n', NULL, &lines, NULL,
-				"print n lines of each tag message",
+		{ OPTION_INTEGER, 'n', NULL, &lines, "n",
+				"print <n> lines of each tag message",
 				PARSE_OPT_OPTARG, NULL, 1 },
 		OPT_BOOLEAN('d', NULL, &delete, "delete tags"),
 		OPT_BOOLEAN('v', NULL, &verify, "verify tags"),