Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3289 Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6808>
It is easier to maintain plain meson.build file instead of a diff. We can edit it directly. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5843>
By default that subproject will be built now instead of requiring the user to provide a location for the SDK.