fixed incorrect message on writing to files when no permission was given (the server does the right job by telling us "file already exists", so we try to open and truncate, getting permission denied).
fixed incorrect message on writing to files when no permission was given (the server does the
right job by telling us "file already exists", so we try to open and truncate, getting permission
denied).

cleahcim/go9p,KevinMGranger/go9p,edahlgren/go9p,larsth/go9p,szhilkin/go9p,cleahcim/go9p,lionkov/ninep,szhilkin/go9p,KevinMGranger/go9p,floren/go9p,henesy/go9p,nilium/go9p,larsth/go9p,nilium/go9p,henesy/go9p,nigifabio/go9p,floren/go9p,nigifabio/go9p