systemd: New systemd-libs package.

If a package requires the systemd-units package, every time the whole systemd
and all its dependencies have to be installed which grows up build environments
for 160MB. To prevent this and save space on disk and time to download and extract
those packages I've moved systemd lib into an own package.

Also fixed a small packaging problem on libudev.
systemd: Add legacy tmpfile for autocreate /run/lock directory.

A lot of services use this directory to put temporary files into it.

Fixes #10291.
initscripts: Fix installation of rc.local script.
Merge remote-tracking branch 'stevee/initscripts-fix'