fib: fix mpls label dpo drop proto

Next drop node should be related to payload protocol.

Type: fix
Signed-off-by: Vladislav Grishenko <themiron@yandex-team.ru>
Change-Id: If12e8dc8b19c61f8c96c275b3f9e565e91ecdbed
diff --git a/src/vnet/dpo/mpls_label_dpo.c b/src/vnet/dpo/mpls_label_dpo.c
index 898ea92..872577d 100644
--- a/src/vnet/dpo/mpls_label_dpo.c
+++ b/src/vnet/dpo/mpls_label_dpo.c
@@ -84,6 +84,7 @@
 
     mld = mpls_label_dpo_alloc();
     mld->mld_flags = flags;
+    mld->mld_payload_proto = payload_proto;
     dtype = mpls_label_dpo_types[flags];
 
     if (MPLS_LABEL_DPO_MAX_N_LABELS < vec_len(label_stack))
@@ -92,13 +93,12 @@
         dpo_stack(dtype,
                   mld->mld_payload_proto,
                   &mld->mld_dpo,
-                  drop_dpo_get(DPO_PROTO_MPLS));
+                  drop_dpo_get(mld->mld_payload_proto));
     }
     else
     {
         mld->mld_n_labels = vec_len(label_stack);
         mld->mld_n_hdr_bytes = mld->mld_n_labels * sizeof(mld->mld_hdr[0]);
-        mld->mld_payload_proto = payload_proto;
 
         /*
          * construct label rewrite headers for each value passed.