more overlay bits

more overlay bits

Although the overlay stuff is destined to be
removed someday, this patch just makes the
use of STATIC_DCL, STATIC_OVL consistent
in the trunk.

[As a side pointless experiment, I was able
 to build a working  8086 port of 3.4.2 after
 this change that worked correctly in limited
 testing right up until it came time to enter
 Ft. Ludios., where it couldn't allocated the
required amount of memory.]