arm: K3: am654: Map common EEPROM data into SRAM scratch space

The board detection scheme employed on various TI EVMs makes use of
SRAM scratch space to share data read from an on-board EEPROM between
the different bootloading stages. Map the associated definition that's
used to locate this data into the SRAM scratch space we use on AM654x.

Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>