Convert CONFIG_RAMBOOT_PBL et al to Kconfig

This converts the following to Kconfig:
   CONFIG_RAMBOOT_PBL
   CONFIG_SYS_FSL_PBL_PBI
   CONFIG_SYS_FSL_PBL_RCW

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/P2041RDB_NAND_defconfig b/configs/P2041RDB_NAND_defconfig
index 90eb53c..1ebc431 100644
--- a/configs/P2041RDB_NAND_defconfig
+++ b/configs/P2041RDB_NAND_defconfig
@@ -10,7 +10,9 @@
 CONFIG_FIT_VERBOSE=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_OF_STDOUT_VIA_ALIAS=y
-CONFIG_SYS_EXTRA_OPTIONS="RAMBOOT_PBL"
+CONFIG_RAMBOOT_PBL=y
+CONFIG_SYS_FSL_PBL_PBI="board/freescale/corenet_ds/pbi.cfg"
+CONFIG_SYS_FSL_PBL_RCW="board/freescale/corenet_ds/rcw_p2041rdb.cfg"
 CONFIG_BOOTDELAY=10
 CONFIG_BOARD_EARLY_INIT_F=y
 CONFIG_BOARD_EARLY_INIT_R=y