mfdeviceprovider: Add support for device update
Similar to the wasapi2 plugin, GstWinRT library will be used for UWP,
and adding new GstWin32DeviceWatcher object implementation for
Win32 desktop application. wasapi2deviceprovider: Add support for device update
... by using newly implemented GstWinRT library libs: Introduce GstWinRT library
Adding a helper library for various WinRT specific implementations.
Currently this library supports only DeviceWatcher abstraction object
which can be used for dynamic device add/remove detection.
See also
https://docs.microsoft.com/en-us/uwp/api/windows.devices.enumeration.devicewatcher?view=winrt-20348