Set up Strike Location is being held over from last mission

[dizzy]

The 'Location' target used to manually select an airstrike coordinate is being held over from one mission to the next on occasion and causes an error window to popup and generally causes issues when readying airplanes. Pretty low priority bug imo cuz it doesnt really negatively impact the game... unless the error is doing something it shouldnt. 

[mobeer]

Repeated in 1.18 - need to have carriers present in two consecutive battles. The selected location and contact report from the first battle are used in the start of the second battle and an error message appears. Seems harmless though.