Bump buidlroot version to 2018.02.6

bsp/buildroot/board/nexbox/a95x/post-build.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+BOARD_DIR="$(dirname $0)"
+MKIMAGE=$HOST_DIR/bin/mkimage
+
+$MKIMAGE -C none -A arm64 -T script -d $BOARD_DIR/boot.txt $BINARIES_DIR/boot.scr
+
+# vendor u-boot uses uImage
+if [ -e $BINARIES_DIR/Image ]; then
+    $MKIMAGE -A arm64 -O linux -T kernel -C none -a 0x1080000 -e 0x1080000 \
+	     -n linux -d $BINARIES_DIR/Image $BINARIES_DIR/uImage
+fi