asus-wmi: drop to_platform_driver macro

to_platform_driver has been defined in platform_device.h, so drop
this repetitive macro in asus-wmi.c.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/asus-wmi.c

@@ -56,9 +56,6 @@ MODULE_AUTHOR("Corentin Chary <corentin.chary@gmail.com>, "
 MODULE_DESCRIPTION("Asus Generic WMI Driver");
 MODULE_LICENSE("GPL");
 
-#define to_platform_driver(drv)					\
-	(container_of((drv), struct platform_driver, driver))
-
 #define to_asus_wmi_driver(pdrv)					\
 	(container_of((pdrv), struct asus_wmi_driver, platform_driver))