ARM: imx: Pick correct eMMC boot partition from ROM log

ARM: imx: Pick correct eMMC boot partition from ROM log

In case the iMX8M boot from eMMC boot partition and the primary image
is corrupted, the BootROM is capable of starting a secondary image in
the other eMMC boot partition as a fallback.

However, the BootROM leaves the eMMC BOOT_PARTITION_ENABLE setting as
it was, i.e. pointing to the boot partition containing the corrupted
image, and the BootROM does not provide any indication that this sort
of fallback occured.

According to AN12853 i.MX ROMs Log Events, Rev. 0, May 2020, it is
possible to determine whether fallback event occurred by parsing the
ROM event log. In case ROM event ID 0x51 is present, fallback event
did occur.

This patch implements ROM event log parsing and search for event ID
0x51 for all iMX8M SoCs, and based on that corrects the eMMC boot
partition selection. This way, the SPL loads the remaining boot
components from the same eMMC boot partition from which it was
started, even in case of the fallback.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Faiz Abbas <faiz_abbas@ti.com>
Cc: Harald Seiler <hws@denx.de>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Ye Li <ye.li@nxp.com>