ovs-vswitchd: Call flow_extract() for resumed packet in nxt_resume().

When the packet-in is resumed by vswitchd, it is not setting the
'dp_packet' offsets, because of which it is crashing while executing
the actions.

Signed-off-by: Numan Siddique <nusiddiq@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

ofproto/ofproto-dpif.c

@@ -4443,6 +4443,9 @@ nxt_resume(struct ofproto *ofproto_,
     dp_packet_init(&packet, pin->public.packet_len);
     dp_packet_put(&packet, pin->public.packet, pin->public.packet_len);
 
+    struct flow headers;
+    flow_extract(&packet, &headers);
+
     /* Execute the datapath actions on the packet. */
     struct dpif_execute execute = {
         .actions = odp_actions.data,