Gadgetfs updates:

 - Resolve a problem that came from a change in the API to AIO:
   kiocb->private type and size changed, but the name remained
   the same ... so GCC wouldn't report pending memory-corruption.

 - Probe the controller at runtime, eliminatingting config-specific
   defines which need to be updated for each new controller.  Rip
   out the old #defines.

 - Use newish APIs to let VBUS current be used to recharge
   batteries (or whatever).

 - Use no_llseek() ... endpoints are pure data streams.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>