libminc: add reboot()
libminc: add reboot()

Change-Id: Ia604e3d57dbcdc25c96c1aa0a263384982311d09

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