aitech.c: Move 'building' assignments outside 'if'
It's a bit cleaner to do assignment before the 'if' than inside it. Change couple of 'building = utype_needs_improvement()' assignments in aitech.c.
It's a bit cleaner to do assignment before the 'if' than inside it. Change couple of 'building = utype_needs_improvement()' assignments in aitech.c.