colibri-imx6ull: enable relocation of fdt and initrd

Remove 'fdt_high' and 'initrd_high' environment variables (set to 0xFFFFFFFF)
from default environment which prevents relocation of FDT and initrd.
Rely on 'bootm_size' value instead to safely relocate kernel, device tree and
initrd.

Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
diff --git a/include/configs/colibri-imx6ull.h b/include/configs/colibri-imx6ull.h
index ea5ba6b..2a76f57 100644
--- a/include/configs/colibri-imx6ull.h
+++ b/include/configs/colibri-imx6ull.h
@@ -40,8 +40,6 @@
 #define MEM_LAYOUT_ENV_SETTINGS \
 	"bootm_size=0x10000000\0" \
 	"fdt_addr_r=0x82100000\0" \
-	"fdt_high=0xffffffff\0" \
-	"initrd_high=0xffffffff\0" \
 	"kernel_addr_r=0x81000000\0" \
 	"pxefile_addr_r=0x87100000\0" \
 	"ramdisk_addr_r=0x82200000\0" \