i.MX SoC update for 5.5: - Add arm64 Kconfig option for the NXP S32 platform. - Drop imx_anatop_usb_chrg_detect_disable() function which becomes unneeded, since all the necessary charger setup is done by the USB PHY driver now. - Add serial number support for i.MX6/7 SoCs by reading 64-bit SoC unique ID from OCOTP block. - Replace i.MX machine specific coherency exit implementation using the generic v7_exit_coherency_flush() function.