[virt-tools-list] [libosinfo] Improve list API

[Christophe Fergeau]

Hi,

libosinfo has various *List classes which basically are a GObject class
wrapping a hash table of objects of a specific type. Each of these classes
implements osinfo_list_new_filtered, osinfo_list_new_copy, ... probably
because of c&p. However, these methods are seldomly used, and are not used
at all on most classes.
It's actually possible to implement these generically in the OsinfoList base
class, this is what this series is doing while deprecating all the other
implementations in derived classes.
I've checked that make check is still working and also ran a quick test
with Boxes.

Christophe