drm/tests: probe-helper: Remove call to drm_kunit_helper_free_device()

Calling drm_kunit_helper_free_device() to clean up the resources
allocated by drm_kunit_helper_alloc_device() is now optional and not
needed in most cases.

Remove it.
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Maíra Canal <mairacanal@riseup.net>
Link: https://lore.kernel.org/r/20230728-kms-kunit-actions-rework-v3-4-952565ccccfe@kernel.orgSigned-off-by: Maxime Ripard <mripard@kernel.org>

drivers/gpu/drm/tests/drm_probe_helper_test.c

@@ -60,13 +60,6 @@ static int drm_probe_helper_test_init(struct kunit *test)
 	return 0;
 }
 
-static void drm_probe_helper_test_exit(struct kunit *test)
-{
-	struct drm_probe_helper_test_priv *priv = test->priv;
-
-	drm_kunit_helper_free_device(test, priv->dev);
-}
-
 typedef struct drm_display_mode *(*expected_mode_func_t)(struct drm_device *);
 
 struct drm_connector_helper_tv_get_modes_test {
@@ -208,7 +201,6 @@ static struct kunit_case drm_test_connector_helper_tv_get_modes_tests[] = {
 static struct kunit_suite drm_test_connector_helper_tv_get_modes_suite = {
 	.name = "drm_connector_helper_tv_get_modes",
 	.init = drm_probe_helper_test_init,
-	.exit = drm_probe_helper_test_exit,
 	.test_cases = drm_test_connector_helper_tv_get_modes_tests,
 };