Introduces a `libraries` variable that contains all libraries in a
list with the following format:
``` meson
libraries = [
[pkg_name, {
'lib': library_object
'gir': [ {full gir definition in a dict } ]
],
....
]
```
It therefore refactors the way we build the gir so that we can reuse the
same information to build them against 'gstreamer-full' in gst-build
when linking statically
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1093>
If we are not receiving a sync-point for a very long time, we need to
keep asking for them. The request-sync-point logic keeps track of how
many keyunitrequests we are allowed to send, but that would not matter
if we don't keep asking.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/930>
