datapath: Only set mark and labels with a commit flag.

datapath: Only set mark and labels with a commit flag.

Upstream commit:
    commit 7d904c7bcd51f72579c0c3134a50896c5a3efb9f
    Author: Jarno Rajahalme <jarno@ovn.org>
    Date:   Tue Jun 21 14:59:38 2016 -0700

    openvswitch: Only set mark and labels with a commit flag.

    Only set conntrack mark or labels when the commit flag is specified.
    This makes sure we can not set them before the connection has been
    persisted, as in that case the mark and labels would be lost in an
    event of an userspace upcall.

    OVS userspace already requires the commit flag to accept setting
    ct_mark and/or ct_labels.  Validate for this in the kernel API.

    Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
    Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>