DVR: run L3 output features

- rename l2_bridged to is_dvr. Including on the ip.api
    this was new in the 18.01 release so no compatability issues.
- steal the free space in vnet_buffer_opaque_t for use with flags.
- run the ipX-output feature arc from the DVR DPO

Change-Id: I040e5976d1dbe076fcdda3a40a7804f56337ce3f
Signed-off-by: Neale Ranns <nranns@cisco.com>
diff --git a/src/vnet/dpo/dpo.c b/src/vnet/dpo/dpo.c
index 1ee0727..51adbc3 100644
--- a/src/vnet/dpo/dpo.c
+++ b/src/vnet/dpo/dpo.c
@@ -40,7 +40,7 @@
 #include <vnet/dpo/interface_rx_dpo.h>
 #include <vnet/dpo/interface_tx_dpo.h>
 #include <vnet/dpo/mpls_disposition.h>
-#include <vnet/dpo/l2_bridge_dpo.h>
+#include <vnet/dpo/dvr_dpo.h>
 #include <vnet/dpo/l3_proxy_dpo.h>
 
 /**
@@ -537,7 +537,7 @@
     interface_rx_dpo_module_init();
     interface_tx_dpo_module_init();
     mpls_disp_dpo_module_init();
-    l2_bridge_dpo_module_init();
+    dvr_dpo_module_init();
     l3_proxy_dpo_module_init();
 
     return (NULL);