ARM: stm32: Auto-detect ROM API table on STM32MP15xx

The ROM API table location is passed to the SPL by BootROM in register r0,
make use of this, store the content of r0 and later use it to access the
ROM API table to determine current boot device.

Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
2 files changed