[media] drivers/media/pci/mantis/mantis_cards: Convert to module_pci_driver

use module_pci_driver instead of init/exit, make code clean

Signed-off-by: Libo Chen <libo.chen@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/pci/mantis/mantis_cards.c b/drivers/media/pci/mantis/mantis_cards.c
index 932a0d7..801fc55 100644
--- a/drivers/media/pci/mantis/mantis_cards.c
+++ b/drivers/media/pci/mantis/mantis_cards.c
@@ -290,18 +290,7 @@
 	.remove		= mantis_pci_remove,
 };
 
-static int mantis_init(void)
-{
-	return pci_register_driver(&mantis_pci_driver);
-}
-
-static void mantis_exit(void)
-{
-	return pci_unregister_driver(&mantis_pci_driver);
-}
-
-module_init(mantis_init);
-module_exit(mantis_exit);
+module_pci_driver(mantis_pci_driver);
 
 MODULE_DESCRIPTION("MANTIS driver");
 MODULE_AUTHOR("Manu Abraham");