I don't know that there's any way to make it go away sooner, but it will abate, and shouldn't be noticeable within a week or 10 days. I have gotten it every time from a cruise, but each successive cruise the effect was less afterwards. I have even had the same thing from a long train ride (i.e. 8 hours)! It's just your inner ear adjusting for the motion, and now having to readjust to solid ground.
I have found just laughing it off helps - it's nothing to worry about, and will go away, really! Just think of it as a lingering memory of your cruise!