scripts: add build-dtb-image.sh, self-contained FIT DTB image builder co-located with metadata#83

bjordiscollaku wants to merge 2 commits intoqualcomm-linux:mainqualcomm-linux/qcom-dtb-metadata:mainfrom

bjordiscollaku:feat/qclinux-fit-image-build-scriptbjordiscollaku/qcom-dtb-metadata:feat/qclinux-fit-image-build-scriptCopy head branch name to clipboard