USB: convert drivers/bluetooth/* to use module_usb_driver()

This converts the drivers in drivers/bluetooth/* to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.

Added bonus is that it removes some unneeded kernel log messages about
drivers loading and/or unloading.

Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: "Gustavo F. Padovan" <padovan@profusion.mobi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>