HDMI : Fix the kernel panic when changing the resolution from big(1080p) to small(480p)

Change-Id: I957d117b4a1a8f9956765864dbd9f314d98c8d6d
Reviewed-on: https://tp-biosrd-v02/gerrit/82325
Reviewed-by: Jamess Huang(黃以民) <Jamess_Huang@asus.com>
Tested-by: Jamess Huang(黃以民) <Jamess_Huang@asus.com>

Author: ashinlin

drivers/gpu/drm/rockchip/rockchip_drm_vop.c

@@ -2113,7 +2113,7 @@ static size_t vop_plane_line_bandwidth(struct drm_plane_state *pstate)
 	int vskiplines = scl_get_vskiplines(src_height, dest_height);
 	size_t bandwidth;
 
-	if (!src_width || !src_height || !dest_width || !dest_height)
+	if (src_width <= 0 || src_height <= 0 || dest_width <= 0 || dest_height <= 0)
 		return 0;
 
 	bandwidth = src_width * bpp / 8;