usb: gadget: Make webcam gadget select USB_LIBCOMPOSITE

Composite gadget support is now available as a library instead of being
built with each gadget. Composite drivers need to select
USB_LIBCOMPOSITE.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/Kconfig

@@ -952,6 +952,7 @@ endif
 config USB_G_WEBCAM
 	tristate "USB Webcam Gadget"
 	depends on VIDEO_DEV
+	select USB_LIBCOMPOSITE
 	help
 	  The Webcam Gadget acts as a composite USB Audio and Video Class
 	  device. It provides a userspace API to process UVC control requests