commit 548dd4b6 upstream.

Do not report errors in write path if port is used as a console as this
may trigger the same error (and error report) resulting in a loop.
Reported-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>