Fix credits position being 1 frame off w/ BG when press/release ACTION

When you pressed and released ACTION to speed up the credits, the
credits position would end up being 1 frame off from the background.

This is due to the fact that we update the tower background after we
update the credits position, so this commit moves the tower background
update before the credits position update.

desktop_version/src/Input.cpp

@@ -2171,6 +2171,12 @@ void gamecompleteinput()
     game.press_action = false;
     game.press_map = false;
 
+    //Do this before we update map.bypos
+    if (!game.colourblindmode)
+    {
+        graphics.updatetowerbackground();
+    }
+
     //Do these here because input comes first
     map.bypos += map.bscroll;
     game.oldcreditposition = game.creditposition;

desktop_version/src/Logic.cpp

@@ -115,11 +115,6 @@ void gamecompletelogic()
         map.bscroll = +1;
     }
 
-    if (!game.colourblindmode)
-    {
-        graphics.updatetowerbackground();
-    }
-
     if (graphics.fademode == 1)
     {
         //Fix some graphical things