ospack: Add fakeroot to development

For some reasons fakeroot was available in 17.09 but it was no longer
available in development ospacks (also used for sysroots).

Fakeroot can be useful in particular in combination with bubblewrap to
install packages in sysroots without using root privileges at any point.

Signed-off-by: Emanuele Aina <emanuele.aina@collabora.com>
Reviewed-by: Frédéric Dalleau <frederic.dalleau@collabora.co.uk>
Differential Revision: https://phabricator.apertis.org/D7427