meson: Fix warning about extract_all_objects usage
We use this because of a meson bug that was fixed in 0.52:
https://mesonbuild.com/Release-notes-for-0-52-0.html#improved-support-for-static-libraries
Bump the requirement and remove the extract_all_objects workaround. This gets rid of a meson warning:
WARNING: extract_all_objects called without setting recursive
keyword argument. Meson currently defaults to
non-recursive to maintain backward compatibility but
the default will be changed in the future.
This should be fine because the Meson in Debian Stable is 0.56 and in Ubuntu Focal (20.04) is 0.53.