games/doomsday: Unbreak on DragonFly (note OSVERSION used without OPSYS)
OPVERSION always requires coupling with OPSYS to be correct, but normally
I let "<" comparison violators go because it never equates to "true" on
DragonFly. This is a rare case where DragonFly needs the comparison to
be true. Add a couple of OPSYS to fix the recent breakage on DragonFly.