fix RTCPeerConnection_addIceCandidate pluginRTCPeerConnection argument is NIL
fix RTCPeerConnection_addIceCandidate pluginRTCPeerConnection argument is NIL

eface2face/cordova-plugin-iosrtc,eface2face/cordova-plugin-iosrtc,hit0907/cordova-plugin-iosrtc,hit0907/cordova-plugin-iosrtc,hit0907/cordova-plugin-iosrtc,eface2face/cordova-plugin-iosrtc