dv: close afbc2 when playing sources with unnecessary el [1/1]

PD#SWPL-915

Problem:
DOLBY only sets the enhancement for the first frame ->
Vd sets cur_dispubf2 according to enhance ->
codec_mm keeps the last frame according to cur_dispbuf2,
so it fails -> AFBC2 access to the released content causes the trigger.

Solution:
close afbc2

Verify:
r321

Change-Id: I03c431a6ea11b8aabf97b1f0b21f717024be2f62
Signed-off-by: Yi Zhou <yi.zhou@amlogic.com>

drivers/amlogic/media/video_sink/video.c

@@ -3891,6 +3891,11 @@ static void vsync_toggle_frame(struct vframe_s *vf)
 			}
 		}
 	}
+
+	/* if el is unnecessary, afbc2 need to be closed */
+	if ((last_el_status == 1) && (vf_with_el == 0))
+		need_disable_vd2 = 1;
+
 	last_el_status = vf_with_el;
 
 	if (((vf->type & VIDTYPE_NO_VIDEO_ENABLE) == 0) &&