usb: gadget: Stall ep0 with OS desc setup when OS desc is not enabled

In some cases, host side stack is sending OS descriptor setup request
which is not handled by composite driver as device level there is no
OS descriptor functionality enabled. This results into OS descriptor
setup is being given to adb function driver (wIindex 5 based
interface). adb function driver does handle it and send request to
user space daemon to queue data but adb daemon is not reading on ep0.
This results into ep0 flow control and stall USB enumeration. Fix this
issue by returning -EINVAL so USB controller driver stall ep0 and
restart it for further USB communication.

Change-Id: I54d889209074410b39018c04ef92b65da5a92bb5
Signed-off-by: Mayank Rana <mrana@codeaurora.org>