Bug#1000217: Ugrade libcap2

[Sebastian Spaeth]

Hi, a new libcap is one of the hurdles towards users being able to wake 
up systems from suspend using systemd user units.

A former libcap developer told us that: we'd need to use a modern enough 
version of libcap & pam_cap.so (version >= 2.58): we have v2.44 in 
Debian (https://tracker.debian.org/pkg/libcap2) (upstream is 2.64).

The systemd issue where this is described is at 
https://github.com/systemd/systemd/issues/17564). Apparently all pieces 
are in place but nobody has put them together, ever.

so, bumping libcap2 would really help there. Is there anything we can do 
to help progress that one?