submodule--helper: free some "displaypath" in "struct update_data"

Make the update_data_release() function free "displaypath" member when
appropriate. The "displaypath" member is always ours, the "const" on
the "char *" was wrong to begin with.

This leaves a leak of "displaypath" in update_submodule(), which as
we'll see in subsequent commits is harder to deal with than this
trivial fix.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Reviewed-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/submodule--helper.c

@@ -1877,7 +1877,7 @@ static void submodule_update_clone_release(struct submodule_update_clone *suc)
 
 struct update_data {
 	const char *prefix;
-	const char *displaypath;
+	char *displaypath;
 	enum submodule_update_type update_default;
 	struct object_id suboid;
 	struct string_list references;
@@ -1915,6 +1915,7 @@ struct update_data {
 
 static void update_data_release(struct update_data *ud)
 {
+	free(ud->displaypath);
 	module_list_release(&ud->list);
 }
 

t/t2403-worktree-move.sh

@@ -2,6 +2,7 @@
 
 test_description='test git worktree move, remove, lock and unlock'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '

t/t7412-submodule-absorbgitdirs.sh

@@ -6,6 +6,7 @@ This test verifies that `git submodue absorbgitdirs` moves a submodules git
 directory into the superproject.
 '
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup a real submodule' '

t/t7419-submodule-set-branch.sh

@@ -9,6 +9,7 @@ This test verifies that the set-branch subcommand of git-submodule is working
 as expected.
 '
 
+TEST_PASSES_SANITIZE_LEAK=true
 TEST_NO_CREATE_REPO=1
 . ./test-lib.sh