docs: Fix checklinks script
docs: Fix checklinks script

Anchors are defined not only as <a name='anchor'... but also
as <tag id='anchor>

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