framework/wifi_manager: Add extern "C" in header
framework/wifi_manager: Add extern "C" in header

- Add extern "C" for __cplusplus in wifi_manager.h

an4967/TizenRT,an4967/TizenRT,pillip8282/TizenRT,sunghan-chang/TizenRT,JeonginKim/TizenRT,jeongchanKim/TizenRT,jeongarmy/TizenRT,an4967/TizenRT,pillip8282/TizenRT,Samsung/TizenRT,HONGCHAEHEE/TizenRT,jeongchanKim/TizenRT,pillip8282/TizenRT,sunghan-chang/TizenRT,davidfather/TizenRT,jeongchanKim/TizenRT,junmin-kim/TizenRT,JeonginKim/TizenRT,pillip8282/TizenRT,pillip8282/TizenRT,sunghan-chang/TizenRT,davidfather/TizenRT,chanijjani/TizenRT,jeongchanKim/TizenRT,chanijjani/TizenRT,jeongchanKim/TizenRT,Samsung/TizenRT,junmin-kim/TizenRT,Samsung/TizenRT,HONGCHAEHEE/TizenRT,chanijjani/TizenRT,JeonginKim/TizenRT,jsdosa/TizenRT,jsdosa/TizenRT,HONGCHAEHEE/TizenRT,junmin-kim/TizenRT,an4967/TizenRT,jeongarmy/TizenRT,Samsung/TizenRT,HONGCHAEHEE/TizenRT,an4967/TizenRT,JeonginKim/TizenRT,jeongchanKim/TizenRT,pillip8282/TizenRT,chanijjani/TizenRT,an4967/TizenRT,junmin-kim/TizenRT,Samsung/TizenRT,an4967/TizenRT,jeongarmy/TizenRT,sunghan-chang/TizenRT,davidfather/TizenRT,JeonginKim/TizenRT,pillip8282/TizenRT,davidfather/TizenRT,jeongarmy/TizenRT,davidfather/TizenRT,sunghan-chang/TizenRT,davidfather/TizenRT,junmin-kim/TizenRT,junmin-kim/TizenRT,JeonginKim/TizenRT,jeongarmy/TizenRT,Samsung/TizenRT,chanijjani/TizenRT,jeongchanKim/TizenRT,jeongarmy/TizenRT,chanijjani/TizenRT,jsdosa/TizenRT,jeongarmy/TizenRT,HONGCHAEHEE/TizenRT,jsdosa/TizenRT,sunghan-chang/TizenRT,junmin-kim/TizenRT,Samsung/TizenRT,HONGCHAEHEE/TizenRT,jsdosa/TizenRT,chanijjani/TizenRT,jsdosa/TizenRT,davidfather/TizenRT,sunghan-chang/TizenRT,jsdosa/TizenRT