cc2420: fix function prototype of set_key
cc2420: fix function prototype of set_key

arurke/contiki,arurke/contiki,arurke/contiki,MohamedSeliem/contiki,arurke/contiki,arurke/contiki,MohamedSeliem/contiki,arurke/contiki,arurke/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki