soc: mediatek: pwrap: fix fatal compiler error

When adding the MT6380 compatible, the sentinel for of_device_id was
deleted, which leades to the following compiler error:
FATAL: drivers/soc/mediatek/mtk-pmic-wrap: struct of_device_id is not terminated with a NULL entry!

Fix this by adding the sentinel again.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

drivers/soc/mediatek/mtk-pmic-wrap.c

@@ -1380,6 +1380,7 @@ static const struct of_device_id of_slave_match_tbl[] = {
 	}, {
 		.compatible = "mediatek,mt6397",
 		.data = &pmic_mt6397,
+	}, {
 		/* sentinel */
 	}
 };