Fix blit thread related deadlocks

Removed unnecessary calls to video_wait_for_blit(), which in
addition to not doing much were also in a race with the
video_blit_memtoscreen() thread to wait for and reset the
blit_data.blit_complete event signalled by blit_thread(),
causing several deadlocks.

src/win/win_ui.c

@@ -166,7 +166,6 @@ static void
 video_toggle_option(HMENU h, int *val, int id)
 {
     startblit();
-    video_wait_for_blit();
     *val ^= 1;
     CheckMenuItem(h, id, *val ? MF_CHECKED : MF_UNCHECKED);
     endblit();
@@ -1467,8 +1466,6 @@ plat_resize(int x, int y)
 
     /* First, see if we should resize the UI window. */
     if (!vid_resize) {
-	video_wait_for_blit();
-
 
 	/* scale the screen base on DPI */
 	if (dpi_scale) {