powerpc/85xx: Add support for booting from NAND on MPC8572DS

Mimic support that exists on MPC8536DS on the MPC8572DS to allow booting
from NAND.

Signed-off-by: Jin Qing <b24347@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/boards.cfg b/boards.cfg
index 0f2e1df..3497408 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -473,6 +473,7 @@
 MPC8569MDS_NAND              powerpc     mpc85xx     mpc8569mds          freescale      -           MPC8569MDS:NAND
 MPC8572DS                    powerpc     mpc85xx     mpc8572ds           freescale      -           MPC8572DS
 MPC8572DS_36BIT              powerpc     mpc85xx     mpc8572ds           freescale      -           MPC8572DS:36BIT
+MPC8572DS_NAND               powerpc     mpc85xx     mpc8572ds           freescale      -           MPC8572DS:NAND
 P1011RDB                     powerpc     mpc85xx     p1_p2_rdb           freescale      -           P1_P2_RDB:P1011
 P1011RDB_NAND                powerpc     mpc85xx     p1_p2_rdb           freescale      -           P1_P2_RDB:P1011,NAND
 P1011RDB_SDCARD              powerpc     mpc85xx     p1_p2_rdb           freescale      -           P1_P2_RDB:P1011,SDCARD