keystone2: config: restructure handling of default env settings

Currently to customize env for various ks2 boards, individual
variables such as NAME_FS etc are defined and included in the
common config.h to define CONFIG_EXTRA_ENV_SETTINGS. This
doesn't scale well if a variable is not applicable on a
specific board. Using this scheme, we have to define variables
with empty value and it's ugly. Instead, to allow board specific
customization of default env variable, define a common
CONFIG_EXTRA_ENV_KS2_SETTINGS for all common variables and define
board specific variables in individual board specific config.h
using CONFIG_EXTRA_ENV_KS2_BOARD_SETTINGS. Use the common and board
specific variables to define CONFIG_EXTRA_ENV_SETTINGS. This way
more variables can be added in future for individual boards
without affecting the other config.h files.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>
diff --git a/include/configs/k2e_evm.h b/include/configs/k2e_evm.h
index 8c3a0c0..6b87f6c 100644
--- a/include/configs/k2e_evm.h
+++ b/include/configs/k2e_evm.h
@@ -17,14 +17,14 @@
 /* U-Boot general configuration */
 #define CONFIG_SYS_PROMPT               "K2E EVM # "
 
-#define KS2_ARGS_UBI   "args_ubi=setenv bootargs ${bootargs} rootfstype=ubifs "\
-		       "root=ubi0:rootfs rootflags=sync rw ubi.mtd=2,2048\0"
-
-#define KS2_FDT_NAME   "name_fdt=k2e-evm.dtb\0"
-#define KS2_ADDR_MON   "addr_mon=0x0c140000\0"
-#define KS2_NAME_MON   "name_mon=skern-k2e-evm.bin\0"
-#define NAME_UBOOT     "name_uboot=u-boot-spi-k2e-evm.gph\0"
-#define NAME_UBI       "name_ubi=k2e-evm-ubifs.ubi\0"
+#define CONFIG_EXTRA_ENV_KS2_BOARD_SETTINGS				\
+	"addr_mon=0x0c140000\0"						\
+	"args_ubi=setenv bootargs ${bootargs} rootfstype=ubifs "	\
+	"root=ubi0:rootfs rootflags=sync rw ubi.mtd=2,2048\0"		\
+	"name_fdt=k2e-evm.dtb\0"					\
+	"name_mon=skern-k2e-evm.bin\0"					\
+	"name_ubi=k2e-evm-ubifs.ubi\0"					\
+	"name_uboot=u-boot-spi-k2e-evm.gph\0"
 
 #include <configs/ks2_evm.h>