Integrate u-boot-seco-imx/seco_lf_v2021.04_develop_video_ym
[iMX6][SECO_CONFIG] delete control on CONFIG_VIDEO for video overlay enablement
This commit reverts 3a5a4321388f347977f344e341fab7ae6222d414 The check on CONFIG_VIDEO was preventing the usage of video overlays, disabling the usage of displays by the kernel; since the usage of CONFIG_VIDEO is now deprecated in favor to CONFIG_DM_VIDEO (needed for IMX IPUv3 graphic), is better to delete those checks. In the (rare) case in which display has to be disbled at kernel, one can use the "no display" option in seco_config.