1. Use pkgrel when depending on systemd-common=...
2. systemd-resolvconf: Don't depend on systemd-common, it's only symlinks.
3. systemd-resolvconf: Don't provide 'resolvconf'. I had included
https://git.archlinux.org/svntogit/packages.git/commit/?h=packages/systemd&id=25987557c0889a54ed5baf0f39b874070e21d894
in my work. That commit is not yet in the repos in Arch, and with
netctl 1.18 it causes an ambiguity in 'base' in Parabola.
4. Backport a commit to fix errors building with glibc 2.28
pkgrel, fix build
1. (not)systemd-resolvconf is only symlinks, use plain
systemd-resolvconf instead.
2. Now that we patch makepkg to treat pkgrel like pkgver in depends, we can
(re-?)add this specificity.
3. Backport a patch to fix the build on glibc 2.28