Merge tag 'u-boot-imx-20220422' of https://gitlab.denx.de/u-boot/custodians/u-boot-imx

u-boot-imx-20220422
-------------------

- Switch to DM_SERIAL
- Drop MMCROOT
- several cleanup

CI: https://source.denx.de/u-boot/custodians/u-boot-imx/-/pipelines/11815

diff --cc arch/arm/Kconfig
Simple merge

diff --cc arch/arm/dts/Makefile
Simple merge

diff --cc arch/arm/mach-imx/imx8m/soc.c
Simple merge

diff --cc include/configs/apalis-imx8.h
Simple merge

diff --cc include/configs/capricorn-common.h
Simple merge

diff --cc include/configs/cgtqmx8.h
Simple merge

diff --cc include/configs/colibri-imx8x.h
Simple merge

diff --cc include/configs/imx8qm_mek.h
Simple merge

diff --cc include/configs/imx8qm_rom7720.h
Simple merge

diff --cc include/configs/imx8qxp_mek.h
Simple merge

diff --cc include/configs/imx8ulp_evk.h
Simple merge