Remove documentation that a feature was missing, because it is not. (#5896)
Remove documentation that a feature was missing, because it is not. (#5896)

MERGED from commit b1bd566a40d3cfe3db51aa1399b293cdbceff185

ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix