GHC build system: Don't install the datafiles twice
GHC build system: Don't install the datafiles twice

adamse/haddock,idontgetoutmuch/haddock,Acidburn0zzz/haddock,niteria/haddock,jstolarek/haddock,randen/haddock,beni55/haddock,mrBliss/haddock,Fuuzetsu/haddock,Wizek/haddock,niteria/haddock,Helkafen/haddock,Helkafen/haddock,mrhania/haddock,sboosali/haddock,Fuuzetsu/haddock,esmolanka/haddock,JPMoresmau/haddock,idontgetoutmuch/haddock,sboosali/haddock,Fuuzetsu/haddock,adamse/haddock,jgm/haddock,adamse/haddock,jgm/haddock,haskell/haddock,Mistuke/haddock,esmolanka/haddock,haskell/haddock,JPMoresmau/haddock,niteria/haddock,sboosali/haddock,Acidburn0zzz/haddock,JPMoresmau/haddock,beni55/haddock,lamefun/haddock,Wizek/haddock,lamefun/haddock,haskell/haddock,randen/haddock,mrBliss/haddock,mrhania/haddock,mrBliss/haddock,Mistuke/haddock,Acidburn0zzz/haddock,beni55/haddock,Mistuke/haddock,idontgetoutmuch/haddock,Wizek/haddock,jstolarek/haddock,mrhania/haddock,Fuuzetsu/haddock,randen/haddock,haskell/haddock,lamefun/haddock,esmolanka/haddock,Helkafen/haddock,haskell/haddock