arm_sdimage.sh: use insert-fs feature
arm_sdimage.sh: use insert-fs feature

Change-Id: Ie8bcbca26d5f530e03dbcb7e55771c5cd29d29f3

veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi