msmnile: Define WIFI_DRIVER_STATE_CTRL_PARAM to write WLAN status

Define path of WIFI_DRIVER_STATE_CTRL_PARAM i.e /dev/wlan
to update status of WLAN Driver on loaded/unloaded by writing
ON/OFF.

Change-Id: I9964a7a3b779f036975b3f461118e86e093a13ea
CRs-Fixed: 2706935