Fix map waypoint loading

[6emmes]

Fixes #1053

[tomsons26]

either g_waypoints or s_waypoints doesn't seem should exist, looks like only g_waypoints should exist

[6emmes]

@tomsons26
Hi, thanks for comment.
Yes, those two variable are very confusing but it seems accurate to the source code (for example WaypointMap::Update).

[tomsons26]

hu my comment edit didn't save..

remove s_waypoints and make

#ifndef GAME_DLL
WaypointMap *g_waypoints = nullptr;
MapCache *g_theMapCache = nullptr;
#endif

code should be only using g_waypoints, there is no duplicate WaypointMap * global