The getty@.service unit already has an ExecStart so we cannot simply set a new
one in order to override it or we will get this error:
systemd[1]: getty@tty1.service: Service has more than one ExecStart= setting, which is only allowed for Type=oneshot services. Refusing.
Instead "reset" ExecStart by setting it to empty which is the systemd way of
doing it.
With kmscon, it is now possible to have a system without X that still
needs the mesa setup in /run/opengl-driver
Signed-off-by: Shea Levy <shea@shealevy.com>
This required some changes to systemd unit handling:
* Add an option to specify that a unit is just a symlink
* Allow specified units to overwrite systemd-provided ones
* Have gettys.target require autovt@1.service instead of getty@1.service
Signed-off-by: Shea Levy <shea@shealevy.com>
