[media] media_device: move allocation out of media_device_*_init

Right now, media_device_pci_init and media_device_usb_init does
media_device allocation internaly. That preents its usage when
the media_device struct is embedded on some other structure.

Move memory allocation outside it, to make it more generic.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/usb/siano/smsusb.c

@@ -367,10 +367,12 @@ static void *siano_media_device_register(struct smsusb_device_t *dev,
 	struct sms_board *board = sms_get_board(board_id);
 	int ret;
 
-	mdev = media_device_usb_init(udev, board->name);
+	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 	if (!mdev)
 		return NULL;
 
+	media_device_usb_init(mdev, udev, board->name);
+
 	ret = media_device_register(mdev);
 	if (ret) {
 		media_device_cleanup(mdev);