[travis] enable Opus codec in "full" builds
[travis] enable Opus codec in "full" builds

cccco/qxmpp,deepak899/qxmpp,gamenet/qxmpp,cccco/qxmpp,LightZam/qxmpp,KangLin/qxmpp,gotomypc/qxmpp,gamenet/qxmpp,gotomypc/qxmpp,olesalscheider/qxmpp,deepak899/qxmpp,Kaffeine/qxmpp,olesalscheider/qxmpp,Ilyatk/qxmpp,Kaffeine/qxmpp,pol51/QXMPP-CMake,ycsoft/qxmpp,ycsoft/qxmpp,Ilyatk/qxmpp,LightZam/qxmpp,ycsoft/qxmpp,Kaffeine/qxmpp,LightZam/qxmpp,KangLin/qxmpp,Ilyatk/qxmpp,kollix/qxmpp,gamenet/qxmpp,pol51/QXMPP-CMake,kollix/qxmpp,deepak899/qxmpp,cccco/qxmpp,olesalscheider/qxmpp,KangLin/qxmpp,kollix/qxmpp,pol51/QXMPP-CMake,gotomypc/qxmpp