openvswitch: Remove unnecessary newlines from OVS_NLERR uses

OVS_NLERR already adds a newline so these just add blank
lines to the logging.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>