Revert "colord: Do not install systemd service unit [1]"

This reverts commit 43cbd6d.

Programs using the GTK+ printing dialog print warnings to the terminal
about the missing service file.

```
** (evince:4561): WARNING **: failed to contact colord: Error calling StartServiceByName for org.freedesktop.ColorManager: GDBus.Error:org.freedesktop.systemd1.LoadFailed: Unit colord.service failed to load: No such file or directory. See system logs and 'systemctl status' for details.
```

colord.be0

@@ -60,8 +60,7 @@ mee_configure() {
         --disable-static \
         --disable-systemd-login \
         --disable-udev \
-        --with-daemon-user=colord \
-        --without-systemdsystemunitdir
+        --with-daemon-user=colord
 }
 
 #mee_build() {