aducrf101: Adjust default buffer sizes to fit better in available RAM
aducrf101: Adjust default buffer sizes to fit better in available RAM

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