* changes:
feat(imx8mq): add BL31 PIE support
refactor(imx8mq): introduce BL31_SIZE
refactor(imx8mq): make use of setup_page_tables()
feat(imx8mq): always set up console
feat(imx8mq): remove empty bl31_plat_runtime_setup
feat(imx8mq): make IMX_BOOT_UART_BASE configurable via build parameter