usb: gadget zero style fixups (mostly whitespace)

Minor updates to "Gadget Zero".

 - Primarily these are whitespace updates to address the fact that since
   this was written, Documentation/CodingStyle was changed to disapprove
   of parts of the original coding style.

 - Update a few comments that weren't quite correct, notably mentioning
   the "autoresume" module parameter.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>