chiliboard config: use CONFIG_DEFAULT_FDT_FILE as env variable

Remove hardcoded ftd file name from environment variables.
Use CONFIG_DEFAULT_FDT_FILE macro instead.

Signed-off-by: Michal Oleszczyk <m.oleszczyk@grinn-global.com>

configs/chiliboard_defconfig

@@ -11,6 +11,7 @@ CONFIG_SPL_WATCHDOG_SUPPORT=y
 CONFIG_SPL_FAT_SUPPORT=y
 CONFIG_BOOTDELAY=1
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
+CONFIG_DEFAULT_FDT_FILE="am335x-chiliboard.dtb"
 CONFIG_SPL=y
 CONFIG_SPL_I2C_SUPPORT=y
 CONFIG_SPL_POWER_SUPPORT=y

include/configs/chiliboard.h

@@ -45,7 +45,7 @@
 	"boot_fdt=try\0" \
 	"console=ttyO0,115200n8\0" \
 	"image=zImage\0" \
-	"fdt_file=am335x-chiliboard.dtb\0" \
+	"fdt_file=" CONFIG_DEFAULT_FDT_FILE "\0" \
 	"ip_dyn=yes\0" \
 	"optargs=\0" \
 	"loadbootscript=" \