moxa: dcd handling of CLOCAL is backwards

We should do hangup on dcd loss if CLOCAL is false not true.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=49911


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>