toradex: set default dhcp distroboot scriptname

Use the same name of DHCP Distroboot script as in regular eMMC case.

Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
diff --git a/include/configs/apalis_t30.h b/include/configs/apalis_t30.h
index b7a2fb6..d1d518a 100644
--- a/include/configs/apalis_t30.h
+++ b/include/configs/apalis_t30.h
@@ -47,7 +47,8 @@
 		"mmc write ${loadaddr} ${uboot_blk} ${blkcnt}\0" \
 
 #define BOARD_EXTRA_ENV_SETTINGS \
-	UBOOT_UPDATE
+	UBOOT_UPDATE \
+	"boot_script_dhcp=boot.scr\0"
 
 #include "tegra-common-post.h"