update 5.0.4 CHANGELOG.md
update 5.0.4 CHANGELOG.md

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