arm: mach-k3: am62: Fixup TF-A/OP-TEE reserved-memory node in FDT

The address we load TF-A and OP-TEE to is configurable by Kconfig
CONFIG_K3_{ATF,OPTEE}_LOAD_ADDR, but the DT nodes reserving this memory
are often statically defined. As these binaries are dynamically loadable,
and in the case of OP-TEE may not even be loaded at all, hard-coding these
addresses is not a hardware description, but rather a configuration.

If the address that U-Boot loaded TF-A or OP-TEE does not match the
address in hard-coded in DT, then fix that node address. This also handles
the case when no reserved memory for these is provided by DT, which is
more correct as explained above.

Add this fixup function, and enable it for AM62.

Signed-off-by: Andrew Davis <afd@ti.com>
Acked-by: Bryan Brattlof <bb@ti.com>
Reviewed-by: Neha Malcom Francis <n-francis@ti.com>