usb: converto drivers/usb/* to use module_platform_driver_probe()

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

Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>