Camera support in Qt6 [Spike]

Qt6 must support camera video capture from one or more cameras.

Camera support should provide similar QML interface as what is currently available on Qt5: https://doc.qt.io/qt-5/qml-qtmultimedia-camera.html.

Camera support must have features:

• List of installed cameras
• Showing video stream from a camera
• Viewfinder settings can be altered

• • Resolution
  • Frame rate
• Recording video from the camera:

• • Support for YUV420 frames
  • Set output file location
  • Supported frame rates
  • Supported audio codecs and descriptions
  • Supported audio sample rates
• Capturing still images from the camera
  • Set output file name