usb: gadget: configfs: handle gadget reset request for android

There is this new mandatory UDC->reset API in v3.18+ kernels,
commit ef979a26 "usb: gadget: add reset API at usb_gadget_driver".

Let android_disconnect handle that for Android, similar to
how composite_disconnect is handling the generic ConfigFS
gadget reset request.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index 52ddfec..bcedccd 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -1602,6 +1602,7 @@
 	.unbind         = configfs_composite_unbind,
 #ifdef CONFIG_USB_CONFIGFS_UEVENT
 	.setup          = android_setup,
+	.reset          = android_disconnect,
 	.disconnect     = android_disconnect,
 #else
 	.setup          = composite_setup,