repack: stop using magic number for ARRAY_SIZE(exts)

We have a static array of extensions, but hardcode the size
of the array in our loops. Let's pull out this magic number,
which will make it easier to change.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/repack.c

@@ -115,7 +115,7 @@ static void remove_redundant_pack(const char *dir_name, const char *base_name)
 
 int cmd_repack(int argc, const char **argv, const char *prefix)
 {
-	const char *exts[2] = {".pack", ".idx"};
+	const char *exts[] = {".pack", ".idx"};
 	struct child_process cmd;
 	struct string_list_item *item;
 	struct argv_array cmd_args = ARGV_ARRAY_INIT;
@@ -258,7 +258,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 	 */
 	failed = 0;
 	for_each_string_list_item(item, &names) {
-		for (ext = 0; ext < 2; ext++) {
+		for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 			char *fname, *fname_old;
 			fname = mkpathdup("%s/%s%s", packdir,
 						item->string, exts[ext]);
@@ -315,7 +315,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 
 	/* Now the ones with the same name are out of the way... */
 	for_each_string_list_item(item, &names) {
-		for (ext = 0; ext < 2; ext++) {
+		for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 			char *fname, *fname_old;
 			struct stat statbuffer;
 			fname = mkpathdup("%s/pack-%s%s",
@@ -335,7 +335,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 
 	/* Remove the "old-" files */
 	for_each_string_list_item(item, &names) {
-		for (ext = 0; ext < 2; ext++) {
+		for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 			char *fname;
 			fname = mkpath("%s/old-pack-%s%s",
 					packdir,