ctk-curses: Introduce CURSES_LIB makefile variable
ctk-curses: Introduce CURSES_LIB makefile variable

This should allow overriding it depending on $(HOST_OS).

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