kmscon: Fix build against systemd 230

From the changelog:

  The compatibility libraries libsystemd-daemon.so,
  libsystemd-journal.so, libsystemd-id128.so, and libsystemd-login.so
  which have been deprecated since systemd-209 have been removed along
  with the corresponding pkg-config files. All symbols provided by those
  libraries are provided by libsystemd.so.

So let's just replace the use of libsystemd-daemon and libsystemd-login
with libsystemd in the configure script until a new version of kmscon
comes along.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>