I can't see how it would have any effect whatsoever.
Whether they returned to Hawaii for this exact problem or not, fact it they did have to return for some software glitch.
The dateline has exact latitude/longitude coordinates, which the GPS and (if the F-22 has it) inertial guidance would feed into the system. I can see this event actually happening.
Oh, yeah I know the GPS will know about the dateline, I just have a hard time believing that it would cause a system crash. It's not all that different than crossing a time zone, only in magnitude, and they would have done that several times already.
For that matter, there'd be no particular purpose in adjusting the time zone each time a boundary is crossed. The only relevant zones are the one you started in and the one you end up in. For the actual time tick, Zulu time is all that matters and it doesn't change. The only thing that changes is the zone, and that's normally only for display purposes.
I'm just not buyin' it yet.