lib was unnecessary, deps for travis included openthreads20 which is now built on ppa with osg-3.4 package. translation: fixed on ppa side

.travis.yml

@@ -33,7 +33,7 @@ addons:
       # Audio & Video
       libsdl2-dev, libqt4-dev, libopenal-dev,
       # The other ones from OpenMW ppa
-      libbullet-dev, libswresample-dev, libopenscenegraph-3.4-130, libopenscenegraph-3.4-dev, libmygui-dev
+      libbullet-dev, libswresample-dev, libopenscenegraph-3.4-dev, libmygui-dev
     ]
 
   coverity_scan: