"Fix" a couple impossible ways for vstat.scaling to be zero.

Seriously, that's not possible.

src/conio/bitmap_con.c

@@ -1663,6 +1663,8 @@ bitmap_largest_mult_inside(int maxwidth, int maxheight)
 		mult = maxwidth / vstat.scrnwidth;
 	else
 		mult = maxheight / vstat.scrnheight;
+	if (mult < 1)
+		mult = 1;
 	for (;mult > 1; mult--) {
 		bitmap_get_scaled_win_size(mult, &w, &h, 0, 0);
 		if (w <= maxwidth && h <= maxheight)

src/conio/x_events.c

@@ -542,7 +542,7 @@ static int video_init()
 	   lot easier. */
 
 	pthread_mutex_lock(&vstatlock);
-	if (x_cvstat.scaling < 1)
+	if (x_cvstat.scaling < 1 || vstat.scaling < 1)
 		x_cvstat.scaling = vstat.scaling = 1;
 	if (ciolib_initial_scaling)
 		x_cvstat.scaling = vstat.scaling = ciolib_initial_scaling;