made cc2420 panid and short address not dependent on endianness
made cc2420 panid and short address not dependent on endianness

MohamedSeliem/contiki,bluerover/6lbr,arurke/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,bluerover/6lbr,bluerover/6lbr,MohamedSeliem/contiki,arurke/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,bluerover/6lbr,bluerover/6lbr,arurke/contiki,arurke/contiki,bluerover/6lbr,bluerover/6lbr,arurke/contiki,arurke/contiki,arurke/contiki