api: autogenerate api trace print/endian

In addition to the external vppapitrace tool, VPP itself supports dumping of API trace files.
In two formats, "custom-dump" and "dump". "dump" gives a human friendly list,
and "custom-dump" is meant to give a list of commands that can be fed to VAT.
This patch only deals with "dump".
Prior to this fix, auto-generation was only done for the basic types.
This fix adds support for any type, including lists, and supports pretty-printing
of enums, strings, IP addresses, MAC addresses and so on.

Usage: api trace dump <api-trace-file>

For example

Change-Id: I4e485680e6dcfce7489299ae6cf31d835071ac40

---------- trace 48 -----------
vl_api_sw_interface_set_flags_t:
  _vl_msg_id: 75
  client_index: 0
  context: 10
  sw_if_index: 1
  flags: IF_STATUS_API_FLAG_ADMIN_UP
---------- trace 49 -----------
vl_api_sw_interface_add_del_address_t:
  _vl_msg_id: 88
  client_index: 0
  context: 11
  sw_if_index: 1
  is_add: 1
  del_all: 0
  prefix: 172.16.1.1/24
---------- trace 51 -----------
vl_api_cli_inband_t:
  _vl_msg_id: 819
  client_index: 0
  context: 13
  cmd: packet-generator capture pg0 pcap /tmp/vpp-unittest-TestMAP-YhcmDX/pg0_out.pcap disable
---------- trace 58 -----------
vl_api_ip_neighbor_add_del_t:
  _vl_msg_id: 199
  client_index: 0
  context: 20
  is_add: 1
  neighbor:
    sw_if_index: 2
    flags: IP_API_NEIGHBOR_FLAG_NONE
    mac_address: 0202.0000.ff02
    ip_address: fd01:2::2

Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: I5556d06008de2762e7c2d35a8b0963ae670b3db1
Type: fix
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/src/vnet/vnet_all_api_h.h b/src/vnet/vnet_all_api_h.h
index ad6dd6a..8399110 100644
--- a/src/vnet/vnet_all_api_h.h
+++ b/src/vnet/vnet_all_api_h.h
@@ -29,6 +29,10 @@
 #include <vlibmemory/vl_memory_api_h.h>
 #endif /* included_from_layer_3 */
 
+#ifdef vl_printfun
+#include <vnet/format_fns.h>
+#endif
+
 #include <vnet/bonding/bond.api.h>
 #include <vnet/devices/af_packet/af_packet.api.h>
 #include <vnet/devices/netmap/netmap.api.h>