Solved with a hack.
oVirt Node Hypervisor release 2.5.0 (2.0.fc17)
Couldn't start a VM because sanlock wasn't running.
Sanlock wasn't running because wdmd wasn't running.
wdmd was running because softdog kernel module wasn't loaded.
As I didn't know of another way of making the change persistent I edited
/config/usr/sbin/ifup and added "/sbin/modprobe softdog" to the top of the
script.
I really think it would be a good idea for the oVirt Node team to add in some persistent
script files that are run at various points in the boot process so that people like me can
add in hacks where needed to make it work.