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>
diff --git a/drivers/usb/gadget/pxa25x_udc.c b/drivers/usb/gadget/pxa25x_udc.c
index d4ca9f1..d52e869 100644
--- a/drivers/usb/gadget/pxa25x_udc.c
+++ b/drivers/usb/gadget/pxa25x_udc.c
@@ -2100,6 +2100,8 @@
 	int retval, irq;
 	u32 chiprev;
 
+	pr_info("%s: version %s\n", driver_name, DRIVER_VERSION);
+
 	/* insist on Intel/ARM/XScale */
 	asm("mrc%? p15, 0, %0, c0, c0" : "=r" (chiprev));
 	if ((chiprev & CP15R0_VENDOR_MASK) != CP15R0_XSCALE_VALUE) {
@@ -2346,18 +2348,7 @@
 	},
 };
 
-static int __init udc_init(void)
-{
-	pr_info("%s: version %s\n", driver_name, DRIVER_VERSION);
-	return platform_driver_probe(&udc_driver, pxa25x_udc_probe);
-}
-module_init(udc_init);
-
-static void __exit udc_exit(void)
-{
-	platform_driver_unregister(&udc_driver);
-}
-module_exit(udc_exit);
+module_platform_driver_probe(udc_driver, pxa25x_udc_probe);
 
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_AUTHOR("Frank Becker, Robert Schwebel, David Brownell");