fix building on systems with realtime
fix building on systems with realtime

cdsteinkuehler/linuxcnc,EqAfrica/machinekit,Cid427/machinekit,cnc-club/linuxcnc,ianmcmahon/linuxcnc-mirror,EqAfrica/machinekit,araisrobo/machinekit,RunningLight/machinekit,aschiffler/linuxcnc,ArcEye/machinekit-testing,ArcEye/machinekit-testing,jaguarcat79/ILC-with-LinuxCNC,ArcEye/machinekit-testing,unseenlaser/machinekit,unseenlaser/linuxcnc,cdsteinkuehler/MachineKit,bmwiedemann/linuxcnc-mirror,ikcalB/linuxcnc-mirror,yishinli/emc2,RunningLight/machinekit,cdsteinkuehler/linuxcnc,EqAfrica/machinekit,strahlex/machinekit,bobvanderlinden/machinekit,unseenlaser/machinekit,EqAfrica/machinekit,jaguarcat79/ILC-with-LinuxCNC,mhaberler/machinekit,EqAfrica/machinekit,cdsteinkuehler/linuxcnc,EqAfrica/machinekit,araisrobo/machinekit,unseenlaser/machinekit,aschiffler/linuxcnc,unseenlaser/linuxcnc,bmwiedemann/linuxcnc-mirror,jaguarcat79/ILC-with-LinuxCNC,yishinli/emc2,bobvanderlinden/machinekit,strahlex/machinekit,ikcalB/linuxcnc-mirror,cnc-club/linuxcnc,mhaberler/machinekit,bobvanderlinden/machinekit,strahlex/machinekit,mhaberler/machinekit,EqAfrica/machinekit,mhaberler/machinekit,araisrobo/linuxcnc,unseenlaser/machinekit,Cid427/machinekit,ArcEye/MK-Qt5,RunningLight/machinekit,araisrobo/machinekit,RunningLight/machinekit,RunningLight/machinekit,cdsteinkuehler/MachineKit,kinsamanka/machinekit,unseenlaser/machinekit,araisrobo/machinekit,ianmcmahon/linuxcnc-mirror,cnc-club/linuxcnc,ArcEye/MK-Qt5,ArcEye/MK-Qt5,ArcEye/machinekit-testing,aschiffler/linuxcnc,ianmcmahon/linuxcnc-mirror,ArcEye/MK-Qt5,ianmcmahon/linuxcnc-mirror,jaguarcat79/ILC-with-LinuxCNC,Cid427/machinekit,narogon/linuxcnc,kinsamanka/machinekit,kinsamanka/machinekit,Cid427/machinekit,narogon/linuxcnc,yishinli/emc2,ArcEye/machinekit-testing,narogon/linuxcnc,ArcEye/MK-Qt5,mhaberler/machinekit,kinsamanka/machinekit,bmwiedemann/linuxcnc-mirror,ArcEye/machinekit-testing,bobvanderlinden/machinekit,kinsamanka/machinekit,araisrobo/linuxcnc,strahlex/machinekit,cnc-club/linuxcnc,RunningLight/machinekit,yishinli/emc2,narogon/linuxcnc,Cid427/machinekit,mhaberler/machinekit,strahlex/machinekit,unseenlaser/machinekit,cdsteinkuehler/linuxcnc,ArcEye/machinekit-testing,araisrobo/machinekit,mhaberler/machinekit,bmwiedemann/linuxcnc-mirror,kinsamanka/machinekit,ikcalB/linuxcnc-mirror,ianmcmahon/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ArcEye/MK-Qt5,araisrobo/linuxcnc,jaguarcat79/ILC-with-LinuxCNC,cdsteinkuehler/linuxcnc,ianmcmahon/linuxcnc-mirror,RunningLight/machinekit,cnc-club/linuxcnc,Cid427/machinekit,bobvanderlinden/machinekit,cdsteinkuehler/MachineKit,bobvanderlinden/machinekit,bmwiedemann/linuxcnc-mirror,EqAfrica/machinekit,ikcalB/linuxcnc-mirror,ianmcmahon/linuxcnc-mirror,unseenlaser/linuxcnc,strahlex/machinekit,bmwiedemann/linuxcnc-mirror,unseenlaser/linuxcnc,cdsteinkuehler/MachineKit,unseenlaser/linuxcnc,araisrobo/machinekit,ArcEye/MK-Qt5,araisrobo/linuxcnc,mhaberler/machinekit,araisrobo/machinekit,narogon/linuxcnc,cdsteinkuehler/linuxcnc,cdsteinkuehler/MachineKit,ArcEye/MK-Qt5,ikcalB/linuxcnc-mirror,strahlex/machinekit,cnc-club/linuxcnc,bobvanderlinden/machinekit,cnc-club/linuxcnc,bmwiedemann/linuxcnc-mirror,ArcEye/machinekit-testing,bobvanderlinden/machinekit,Cid427/machinekit,Cid427/machinekit,araisrobo/machinekit,unseenlaser/machinekit,ikcalB/linuxcnc-mirror,aschiffler/linuxcnc,araisrobo/machinekit,kinsamanka/machinekit,aschiffler/linuxcnc,araisrobo/linuxcnc,kinsamanka/machinekit,cdsteinkuehler/MachineKit,unseenlaser/machinekit,RunningLight/machinekit