Add API calls for packet generator

Added new API to:
- create packet generator interface
- enable packet generator per stream or all
- capture into file

Change-Id: I0e6c1f28069853e4b26f0dc9d282353b0b7f6512
Signed-off-by: Pavel Kotucek <pkotucek@cisco.com>
diff --git a/vnet/vnet/pg/pg.h b/vnet/vnet/pg/pg.h
index 750e7f7..54c270f 100644
--- a/vnet/vnet/pg/pg.h
+++ b/vnet/vnet/pg/pg.h
@@ -352,4 +352,16 @@
 					  void * fixed_packet_data,
 					  void * fixed_packet_data_mask);
 
+void pg_enable_disable (u32 stream_index, int is_enable);
+
+typedef struct {
+  u32  hw_if_index;
+  u32  dev_instance;
+  u8   is_enabled;
+  u8 * pcap_file_name;
+  u32  count;
+} pg_capture_args_t;
+
+clib_error_t * pg_capture (pg_capture_args_t *a);
+
 #endif /* included_vlib_pg_h */