vlib: add flag to explicitelly mark nodes which can init per-node packet trace

Type: feature

Change-Id: I913f08383ee1c24d610c3d2aac07cef402570e2c
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vnet/devices/virtio/node.c b/src/vnet/devices/virtio/node.c
index 8441250..9711c7a 100644
--- a/src/vnet/devices/virtio/node.c
+++ b/src/vnet/devices/virtio/node.c
@@ -398,6 +398,7 @@
   .name = "virtio-input",
   .sibling_of = "device-input",
   .format_trace = format_virtio_input_trace,
+  .flags = VLIB_NODE_FLAG_TRACE_SUPPORTED,
   .type = VLIB_NODE_TYPE_INPUT,
   .state = VLIB_NODE_STATE_INTERRUPT,
   .n_errors = VIRTIO_INPUT_N_ERROR,