MLK-19064 imx8qm: Add secure boot environment

MLK-19064 imx8qm: Add secure boot environment

Add the secure boot relevant environment variables to ARM2 and MEK.
When CONFIG_AHAB_BOOT is enabled, we will switch to boot flow:
1. Load the signed OS container to address 0x88000000
2. Using auth_cntr to authenticate the OS container. It will load the
   kernel and FDT to destination addresses.
3. Using booti to boot kernel.

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit eb47b72c1c89deddeaa3b3618d8c28aca05cd4ad)
(cherry picked from commit e469bf980df3fa5c7d4e059aaaed4db296a0b002)