Travis: Fix brew

.travis.yml

@@ -1,6 +1,8 @@
 language: cpp
 compiler: gcc
 matrix:
+    exclude:
+        - os: linux
     include:
         - os: linux
           env: TARGET_OS=linux
@@ -26,7 +28,7 @@ install:
           if [ $TARGET_OS == win64 ]; then sudo apt-get install -y mingw64-x-qt mingw64-x-sdl mingw64-x-libvorbis mingw64-x-fluidsynth mingw64-x-stk mingw64-x-glib2 mingw64-x-portaudio mingw64-x-libsndfile mingw64-x-fftw mingw64-x-flac mingw64-x-fltk mingw64-x-libsamplerate mingw64-x-pkgconfig mingw64-x-binutils mingw64-x-gcc mingw64-x-runtime mingw64-x-libgig; fi;
       fi
     - if [ $TRAVIS_OS_NAME == osx ]; then
-          brew upgrade qt libsndfile fftw libvorbis libogg jack sdl libsamplerate stk fluid-synth portaudio fltk;
+          brew install qt libsndfile fftw libvorbis libogg jack sdl libsamplerate stk fluid-synth portaudio fltk;
       fi
 before_script:
     - mkdir build && cd build