armv7r: K3: Allow SPL to run only on core 0

armv7r: K3: Allow SPL to run only on core 0

Based on the MCU R5 efuse settings, R5F cores in MCU domain
either work in split mode or in lock step mode.

If efuse settings are in lockstep mode: ROM release R5 cores
and SPL continues to run on the R5 core is lockstep mode.

If efuse settings are in split mode: ROM releases both the R5
cores simultaneously and allow SPL to run on both the cores.
In this case it is bootloader's responsibility to detect core
1 and park it. Else both the core will be running bootloader
independently which might result in an unexpected behaviour.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>