USB: Push BKL on open down into the drivers

Straightforward push into the drivers to allow
auditing individual drivers separately

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>