Revert "usb: gadget: Add function wakeup support"

This reverts commit c3f39268 which is
commit f0db885f upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I1f90ccbe0ab8ed0869db654dfe43b0573c55ec3c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>