v2.4-stm32mp-r2

STM32MP release v2.4-stm32mp-r2

DDR: DQS Tuning: Add RVTRN (for LPDDR2 / LPDDR3)
Enable ETH PTP clock tree by default on STM32MP15 boards
Manage backup registers security at BL32 level
Fix the shutdown via PMIC switch off
Improve boot time in FIP mode using mmc interfaces
Fix RTC clock rate
Display bootrom authentication trace
Fixes