Fix a typo in a function prototype in game.h

This is a merge of 909e694 from baseq2, original
written by svdijk.
Remove superflous statement

This was originaly committed into baseq2 by svdijk
Fix help computer and inventory updates when already opened

These changes ware originally committed by svdijk into baseq2
as reveison 6f6c9a1 to 20110fa.