usb: musb: cleanup while removing musb omap glue driver

No functional change. Just replaced the call to platform_device_del and
platform_device_put with platform_device_unregister.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/musb/omap2430.c

@@ -509,8 +509,7 @@ static int __devexit omap2430_remove(struct platform_device *pdev)
 	struct omap2430_glue		*glue = platform_get_drvdata(pdev);
 
 	cancel_work_sync(&glue->omap_musb_mailbox_work);
-	platform_device_del(glue->musb);
-	platform_device_put(glue->musb);
+	platform_device_unregister(glue->musb);
 
 	return 0;
 }