media: Check audioType first at Decoder::create
media: Check audioType first at Decoder::create

If audioType is AUDIO_TYPE_UNKNOWN, just return nullptr.

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