Add DRAM settings for 1 GiB variant of DH STM32MP13xx DHCOR SoM and support for SoM DRAM coding HW straps decoding and automatic DRAM configuration selection. Enable CONFIG_BOARD_EARLY_INIT_F on all STM32MP1 DHSOM, as it is required for the HW straps decoding. Signed-off-by: Marek Vasut <marek.vasut@mailbox.org> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>