Try Qt5_ROOT instead

.github/workflows/sdrangel.yml

@@ -30,12 +30,10 @@ jobs:
         run: brew update
       - name: Install brew packages
         run: brew install nasm boost hidapi libusb fftw ffmpeg faad2 opencv zlib airspy airspyhf hackrf rtl-sdr libbladerf uhd soapysdr
-      - name: Unstall brew's Qt6, so we use 5.15 installed above
-        run: brew uninstall qt
       - name: build sdrangel on Mac
         run: |
           mkdir build && cd build
-          cmake .. -DCMAKE_BUILD_TYPE=Release -DARCH_OPT=nehalem -DDEBUG_OUTPUT=ON  -DENABLE_MIRISDR=OFF -DBUILD_SERVER=OFF -DENABLE_EXTERNAL_LIBRARIES=AUTO -DBUNDLE=ON -DPKG_CONFIG_USE_CMAKE_PREFIX_PATH=TRUE -DCMAKE_PREFIX_PATH="$QT_ROOT_DIR"
+          cmake .. -DCMAKE_BUILD_TYPE=Release -DARCH_OPT=nehalem -DDEBUG_OUTPUT=ON  -DENABLE_MIRISDR=OFF -DBUILD_SERVER=OFF -DENABLE_EXTERNAL_LIBRARIES=AUTO -DBUNDLE=ON -DPKG_CONFIG_USE_CMAKE_PREFIX_PATH=TRUE -DQt5_ROOT=$QT_ROOT_DIR
           make package -j4
      
   build: