Correct errno on client disconnection is -ENODEV not -EBUSY

Cc: <stable@vger.kernel.org> #4.3+
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>