CHROMIUM: usb: gadget: f_accessory: add .raw_request callback

After this upstream commit: 3c86726,
.raw_request is mandatory in hid_ll_driver structure, hence add an empty
raw_request() function.

BUG=chrome-os-partner:49140
TEST=none

Change-Id: Idd0bbe6960aad2c557376e4a24827d7e1df8e023
Signed-off-by: Mark Kuo <mkuo@nvidia.com>
Reviewed-on: https://chromium-review.googlesource.com/321038
Commit-Ready: Andrew Bresticker <abrestic@chromium.org>
Tested-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>

drivers/usb/gadget/function/f_accessory.c

@@ -404,12 +404,19 @@ static void acc_hid_close(struct hid_device *hid)
 {
 }
 
+int acc_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
+	__u8 *buf, size_t len, unsigned char rtype, int reqtype)
+{
+	return 0;
+}
+
 static struct hid_ll_driver acc_hid_ll_driver = {
 	.parse = acc_hid_parse,
 	.start = acc_hid_start,
 	.stop = acc_hid_stop,
 	.open = acc_hid_open,
 	.close = acc_hid_close,
+	.raw_request = acc_hid_raw_request,
 };
 
 static struct acc_hid_dev *acc_hid_new(struct acc_dev *dev,