Drop dupe and commented out builds for arm

roles/netbootxyz/templates/menu/linux-arm.ipxe.j2

@@ -12,13 +12,6 @@ item debian ${space} Debian
 item fedora ${space} Fedora
 item rhel ${space} Red Hat Enterprise Linux
 item rockylinux ${space} Rocky Linux
-#item --gap All Others:
-#item coreos ${space} Fedora CoreOS (Preview)
-#item flatcar ${space} Flatcar
-#item nixos ${space} NixOS
-item rhel ${space} Red Hat Enterprise Linux
-#item tinycore ${space} Tiny Core Linux
-#item ubuntu ${space} Ubuntu
 choose menu || goto linux_exit
 echo ${cls}
 goto ${menu} ||