media: exynos4-is: Fix a reference count leak due to pm_runtime_get_sync

On calling pm_runtime_get_sync() the reference count of the device
is incremented. In case of failure, decrement the
reference count before returning the error.
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/exynos4-is/media-dev.c

@@ -509,8 +509,10 @@ static int fimc_md_register_sensor_entities(struct fimc_md *fmd)
 		return -ENXIO;
 
 	ret = pm_runtime_get_sync(fmd->pmf);
-	if (ret < 0)
+	if (ret < 0) {
+		pm_runtime_put(fmd->pmf);
 		return ret;
+	}
 
 	fmd->num_sensors = 0;