powerpc/mpc85xx: SECURE BOOT- Add NAND secure boot target for BSC9132QDS

In case of secure boot from NAND, the DDR is initialized by the
BootROM using the config words (CF_WORDS) in the CF_HEADER
and u-boot image is copied from NAND to DDR by the BootROM.
So, CONFIG_SYS_RAMBOOT has been defined for Secure Boot from NAND

Signed-off-by: Aneesh Bansal <aneesh.bansal@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/boards.cfg b/boards.cfg
index 2e0bee7..4c9a1a4 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -765,6 +765,8 @@
 Active  powerpc     mpc85xx        -           freescale       bsc9132qds          BSC9132QDS_SDCARD_DDRCLK133_SECURE   BSC9132QDS:BSC9132QDS,SDCARD,SYS_CLK_100_DDR_133,SECURE_BOOT                                                                      Aneesh Bansal <aneesh.bansal@freescale.com>
 Active  powerpc     mpc85xx        -           freescale       bsc9132qds          BSC9132QDS_SPIFLASH_DDRCLK100_SECURE BSC9132QDS:BSC9132QDS,SPIFLASH,SYS_CLK_100_DDR_100,SECURE_BOOT                                                                    Aneesh Bansal <aneesh.bansal@freescale.com>
 Active  powerpc     mpc85xx        -           freescale       bsc9132qds          BSC9132QDS_SPIFLASH_DDRCLK133_SECURE BSC9132QDS:BSC9132QDS,SPIFLASH,SYS_CLK_100_DDR_133,SECURE_BOOT                                                                    Aneesh Bansal <aneesh.bansal@freescale.com>
+Active  powerpc     mpc85xx        -           freescale       bsc9132qds          BSC9132QDS_NAND_DDRCLK100_SECURE     BSC9132QDS:BSC9132QDS,NAND_SECBOOT,SYS_CLK_100_DDR_100,SECURE_BOOT                                                                Aneesh Bansal <aneesh.bansal@freescale.com>
+Active  powerpc     mpc85xx        -           freescale       bsc9132qds          BSC9132QDS_NAND_DDRCLK133_SECURE     BSC9132QDS:BSC9132QDS,NAND_SECBOOT,SYS_CLK_100_DDR_133,SECURE_BOOT                                                                Aneesh Bansal <aneesh.bansal@freescale.com>
 Active  powerpc     mpc85xx        -           freescale       c29xpcie            C29XPCIE                             C29XPCIE:C29XPCIE,36BIT                                                                                                           Po Liu <po.liu@freescale.com>
 Active  powerpc     mpc85xx        -           freescale       c29xpcie            C29XPCIE_NAND                        C29XPCIE:C29XPCIE,36BIT,NAND                                                                                                      Po Liu <po.liu@freescale.com>
 Active  powerpc     mpc85xx        -           freescale       c29xpcie            C29XPCIE_SPIFLASH                    C29XPCIE:C29XPCIE,36BIT,SPIFLASH                                                                                                  Po Liu <po.liu@freescale.com>