With:

b8c725e736 (HEAD, origin/master, origin/HEAD) Merge tag 'u-boot-stm32-20210106' of https://gitlab.denx.de/u-boot/custodians/u-boot-stm
ec4efd5ae7 ARM: dts: stm32: Fix GPIO hog flags on DHCOM DRC02
1a6de002e5 ARM: dts: stm32: Fix GPIO hog flags on DHCOM PicoITX
c2d80bbde8 Merge tag 'ti-v2021.01-rc5' of https://gitlab.denx.de/u-boot/custodians/u-boot-ti
a8ef64e4ef Nokia RX-51: Decrease i2c speed to 100000
d8ab0fe5b5 image: support board_fit_config_name_match
f14e6eec6c image: cleanup pre-processor usage
62b07b5173 (tag: v2021.01-rc5) Prepare v2021.01-rc5

And:

#!/bin/sh
# Copyright (C) 2021 Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

set -e

sunxi_defconfigs="\
    A10-OLinuXino-Lime_defconfig \
    A10s-OLinuXino-M_defconfig \
    A13-OLinuXino_defconfig \
    A13-OLinuXinoM_defconfig \
    A20-OLinuXino-Lime_defconfig \
    A20-OLinuXino-Lime2_defconfig \
    A20-OLinuXino-Lime2-eMMC_defconfig \
    A20-OLinuXino_MICRO_defconfig \
    Bananapi_defconfig \
    Bananapro_defconfig \
    CHIP_defconfig \
    Cubieboard_defconfig \
    Cubieboard2_defconfig \
    Cubietruck_defconfig \
    Linksprite_pcDuino_defconfig \
    Linksprite_pcDuino3_defconfig \
    Linksprite_pcDuino3_Nano_defconfig \
    orangepi_2_defconfig \
    orangepi_one_defconfig \
    orangepi_pc_defconfig \
    orangepi_plus_defconfig \
" 

ti_soc_defconfigs="\
    am335x_evm_defconfig \
    chiliboard_defconfig \
    omap3_beagle_defconfig \
    omap4_panda_defconfig \
" 

imx_defconfigs="\
    tbs2910_defconfig \
" 

imx_extra_defconfigs="\
    mx6cuboxi_defconfig \
    nitrogen6q_defconfig \
    udoo_defconfig \
    usbarmory_defconfig \
    wandboard_defconfig \
" 

check_defconfig()
{
    defconfig="$1" 

    ARCH=arm CROSS_COMPILE=arm-none-eabi- make "${defconfig}" 2>&1 > /dev/null
    grep "CONFIG_DM_VIDEO" 2>&1 > /dev/null .config  ; ret=$?
    if [ ${ret} -eq 0 ] ; then
    echo "  ${defconfig}: OK" 
    else
    echo "  ${defconfig}: Missing CONFIG_DM_VIDEO: no Display connector?" 
    fi

}

echo "checking uboot4extlinux-sunxi:" 
for defconfig in ${sunxi_defconfigs} ; do
    check_defconfig "${defconfig}" 
done

echo "checking uboot4extlinux-ti-soc:" 
for defconfig in ${ti_soc_defconfigs} ; do
    check_defconfig "${defconfig}" 
done

echo "checking uboot4extlinux-imx:" 
for defconfig in ${imx_defconfigs} ; do
    check_defconfig "${defconfig}" 
done

echo "checking extra boards (to be added from old u-boot packages) for uboot4extlinux-imx:" 
for defconfig in ${imx_extra_defconfigs} ; do
    check_defconfig "${defconfig}" 
done

We have:

checking uboot4extlinux-sunxi:
  A10-OLinuXino-Lime_defconfig: OK
  A10s-OLinuXino-M_defconfig: OK
  A13-OLinuXino_defconfig: OK
  A13-OLinuXinoM_defconfig: OK
  A20-OLinuXino-Lime_defconfig: OK
  A20-OLinuXino-Lime2_defconfig: OK
  A20-OLinuXino-Lime2-eMMC_defconfig: OK
  A20-OLinuXino_MICRO_defconfig: OK
  Bananapi_defconfig: OK
  Bananapro_defconfig: OK
  CHIP_defconfig: OK
  Cubieboard_defconfig: OK
  Cubieboard2_defconfig: OK
  Cubietruck_defconfig: OK
  Linksprite_pcDuino_defconfig: OK
  Linksprite_pcDuino3_defconfig: OK
  Linksprite_pcDuino3_Nano_defconfig: OK
  orangepi_2_defconfig: OK
  orangepi_one_defconfig: OK
  orangepi_pc_defconfig: OK
  orangepi_plus_defconfig: OK
checking uboot4extlinux-ti-soc:
  am335x_evm_defconfig: OK
  chiliboard_defconfig: OK
  omap3_beagle_defconfig: OK
  omap4_panda_defconfig: OK
checking uboot4extlinux-imx:
  tbs2910_defconfig: OK
checking extra boards (to be added from old u-boot packages) for uboot4extlinux-imx:
  mx6cuboxi_defconfig: OK
  nitrogen6q_defconfig: OK
  udoo_defconfig: OK

So we're good.

We can safely assume that display does work or will work in u-boot after some time on all the boards we support in the uboot4extlinux packages.