fetch-pack: use file-scope static struct for fsck_options

Change code added in 5476e1efde (fetch-pack: print and use dangling
.gitmodules, 2021-02-22) so that we use a file-scoped "static struct
fsck_options" instead of defining one in the "fsck_gitmodules_oids()"
function.

We use this pattern in all of
builtin/{fsck,index-pack,mktag,unpack-objects}.c. It's odd to see
fetch-pack be the odd one out. One might think that we're using other
fsck_options structs in fetch-pack, or doing on fsck twice there, but
we're not.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/fetch-pack.c b/fetch-pack.c
index 82c3c2c..229fd8e 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -38,6 +38,7 @@
 static int advertise_sid;
 static struct shallow_lock shallow_lock;
 static const char *alternate_shallow_file;
+static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT;
 static struct strbuf fsck_msg_types = STRBUF_INIT;
 static struct string_list uri_protocols = STRING_LIST_INIT_DUP;
 
@@ -991,15 +992,14 @@
 {
 	struct oidset_iter iter;
 	const struct object_id *oid;
-	struct fsck_options fo = FSCK_OPTIONS_STRICT;
 
 	if (!oidset_size(gitmodules_oids))
 		return;
 
 	oidset_iter_init(gitmodules_oids, &iter);
 	while ((oid = oidset_iter_next(&iter)))
-		register_found_gitmodules(&fo, oid);
-	if (fsck_finish(&fo))
+		register_found_gitmodules(&fsck_options, oid);
+	if (fsck_finish(&fsck_options))
 		die("fsck failed");
 }