Fix compile failure if both MAKEANDPLAY and NO_CUSTOM_LEVELS are defined

I don't know why you would have to have both defined simultaneously, but
now you can.

The compile fail was caused by the fact that if both were defined, then
there would be an expression like this in Map.cpp:

    switch (t)
    {
    case 0:
    }

which is an invalid expression.

The solution is to put 'case 0:' into the MAKEANDPLAY ifdef-guard as
well.

desktop_version/src/Map.cpp

@@ -1297,8 +1297,8 @@ void mapclass::loadlevel(int rx, int ry)
 
 	switch(t)
 	{
-	case 0:
 #if !defined(MAKEANDPLAY)
+	case 0:
 	case 1: //World Map
 		tileset = 1;
 		extrarow = 1;