Merge tag 'u-boot-imx-next-20240603' of https://gitlab.denx.de/u-boot/custodians/u-boot-imx into next

CI: https://source.denx.de/u-boot/custodians/u-boot-imx/-/pipelines/20956

- Support different RAM sizes on imx8m phycoce boards.
- Support new toradex variants.
- Support Samsung 4GB DDR and Realtek RTL8211E PHY on imx8mm-cl-iot-gate.
- Convert imx8mm-phycore and imx8mp-phycore boards to use OF_UPSTREAM.