.travis.yml: Remove superfluous environments for qt4
.travis.yml: Remove superfluous environments for qt4

LightZam/qxmpp,LightZam/qxmpp,Kaffeine/qxmpp,Kaffeine/qxmpp,Kaffeine/qxmpp,KangLin/qxmpp,KangLin/qxmpp,KangLin/qxmpp,LightZam/qxmpp