Use ifdef _POSIX_PRIORITY_SCHEDULING to protect sched_setscheduler
Use ifdef _POSIX_PRIORITY_SCHEDULING to protect sched_setscheduler

ardje/luaposix,rrthomas/luaposix,zevv/luaposix,jimmyharris/luaposix,jimmyharris/luaposix,snegovick/luaposix,snegovick/luaposix,luaposix/luaposix,zevv/luaposix,rrthomas/luaposix,ardje/luaposix