Fix out-of-bounds array access in findstartpoint()

Out-of-bounds array access is Undefined Behavior, which means Bad
Things.

In this particular case, it was indexing an array by using the
`testeditor` variable. Which is fine, except it was indexing that array
*in a conditional that only happens if `testeditor` is -1*. So it was
indexing an array at position -1, which is Out of Bounds and is Not
Good.

desktop_version/src/editor.cpp

@@ -1595,7 +1595,7 @@ void editorclass::findstartpoint(Game& game)
         game.edsavery = 100;
         game.edsavegc = 0;
         game.edsavey--;
-        game.edsavedir=1-edentity[testeditor].p1;
+        game.edsavedir=1;
     }
     else
     {