openvswitch: fix trivial comment typo

The commit 33db4125 ("openvswitch: Rename LABEL->LABELS") left
over an old OVS_CT_ATTR_LABEL instance, fix it.

Fixes: 33db4125 ("openvswitch: Rename LABEL->LABELS")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NJoe Stringer <joe@ovn.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/uapi/linux/openvswitch.h

@@ -628,7 +628,7 @@ struct ovs_action_hash {
  * @OVS_CT_ATTR_MARK: u32 value followed by u32 mask. For each bit set in the
  * mask, the corresponding bit in the value is copied to the connection
  * tracking mark field in the connection.
- * @OVS_CT_ATTR_LABEL: %OVS_CT_LABELS_LEN value followed by %OVS_CT_LABELS_LEN
+ * @OVS_CT_ATTR_LABELS: %OVS_CT_LABELS_LEN value followed by %OVS_CT_LABELS_LEN
  * mask. For each bit set in the mask, the corresponding bit in the value is
  * copied to the connection tracking label field in the connection.
  * @OVS_CT_ATTR_HELPER: variable length string defining conntrack ALG.