usb: chipidea: usbmisc: use module_platform_driver

This patch converts the driver to use the module_platform_driver
macro which makes the code smaller and a bit simpler.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Michael Grzeschik <mgr@pengutronix.de>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>