ofp-actions: Fix userspace support for mpls_ttl.

Currently mpls_ttl is ignored when a flow is added because MFF_MPLS_TTL is
not handled in nx_put_raw().

This commit adds the correct handling of MFF_MPLS_TTL in nx_put_raw().

Fixes: bef3f46 ("openflow: Support matching and modifying MPLS TTL field.")
Signed-off-by: Timothy Redaelli <tredaelli@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

lib/nx-match.c

@@ -1110,6 +1110,11 @@ nx_put_raw(struct ofpbuf *b, enum ofp_version oxm, const struct match *match,
                       mpls_lse_to_bos(flow->mpls_lse[0]));
         }
 
+        if (match->wc.masks.mpls_lse[0] & htonl(MPLS_TTL_MASK)) {
+            nxm_put_8(&ctx, MFF_MPLS_TTL, oxm,
+                      mpls_lse_to_ttl(flow->mpls_lse[0]));
+        }
+
         if (match->wc.masks.mpls_lse[0] & htonl(MPLS_LABEL_MASK)) {
             nxm_put_32(&ctx, MFF_MPLS_LABEL, oxm,
                        htonl(mpls_lse_to_label(flow->mpls_lse[0])));