MNG-5771 disabled modello xdoc/xsd for core extensions mdo
MNG-5771 disabled modello xdoc/xsd for core extensions mdo

... hopefully fixes maven site generation

Signed-off-by: Igor Fedorenko <e2440853d50b45e1b03436d941fd254bdd25413b@apache.org>

vedmishr/demo1,kidaa/maven-1,karthikjaps/maven,trajano/maven,keith-turner/maven,changbai1980/maven,wangyuesong0/maven,stephenc/maven,mcculls/maven,apache/maven,lbndev/maven,skitt/maven,wangyuesong/maven,rogerchina/maven,barthel/maven,pkozelka/maven,ChristianSchulte/maven,likaiwalkman/maven,wangyuesong/maven,likaiwalkman/maven,josephw/maven,dsyer/maven,Mounika-Chirukuri/maven,stephenc/maven,ChristianSchulte/maven,wangyuesong0/maven,changbai1980/maven,barthel/maven,trajano/maven,atanasenko/maven,mizdebsk/maven,cstamas/maven,keith-turner/maven,mcculls/maven,olamy/maven,gorcz/maven,njuneau/maven,wangyuesong/maven,rogerchina/maven,Mounika-Chirukuri/maven,Mounika-Chirukuri/maven,xasx/maven,mizdebsk/maven,dsyer/maven,xasx/maven,karthikjaps/maven,cstamas/maven,atanasenko/maven,olamy/maven,mizdebsk/maven,karthikjaps/maven,skitt/maven,ChristianSchulte/maven,apache/maven,dsyer/maven,likaiwalkman/maven,keith-turner/maven,josephw/maven,trajano/maven,mcculls/maven,aheritier/maven,josephw/maven,changbai1980/maven,gorcz/maven,aheritier/maven,barthel/maven,skitt/maven,lbndev/maven,kidaa/maven-1,stephenc/maven,aheritier/maven,vedmishr/demo1,rogerchina/maven,xasx/maven,gorcz/maven,njuneau/maven,olamy/maven,vedmishr/demo1,cstamas/maven,njuneau/maven,pkozelka/maven,kidaa/maven-1,pkozelka/maven,lbndev/maven,atanasenko/maven,apache/maven,wangyuesong0/maven