enterprise-registry: remove sub category
enterprise-registry: remove sub category

bq-xiao/docs,michelleN/docs,robszumski/docs,coreos/docs,wli6/docs,marineam/coreos-docs,ionave/docs,mjg59/docs,ksmaheshkumar/docs-2,joshix/docs,jdloft/docs,jonboulle/docs,hkjn/docs-1,iankronquist/docs,mischief/coreos-docs,atxwebs/docs,skynet/docs,endocode/coreos-docs