CMake Error if gstreamer_gl_wayland (or gl_x11) feature is enabled

Noticed that if attempt to manually force-set -DQT_FEATURE_gstreamer_gl_wayland=ON (or x11=ON) using 6.8.0_beta2 that it results in an error about GlWayland or GlX11 not being found (see qtmultimedia.log) despite all the components being present on the system.

Implies that auto-detection is likely failing as well.

After inspection, in FindGStreamer.cmake there is:
DEPENDENCIES GStreamer::Video GStreamer::Base GStreamer::Core GStreamer::Gl XCB::XCB )
DEPENDENCIES GStreamer::Video GStreamer::Base GStreamer::Core GStreamer::Gl Wayland::Client )

But there is no qt_find_package statement for xcb nor wayland that I can see, so the condition is likely always false. As a test, removing the last dependency in both allowed it to compile successfully.