VPP-118: add support for variable length arrays to jvpp

* extends VPP's message definition language with the following syntax:

u32 count:
u8 array[count];

which is traslated to:

u32 count;
u8 array[0];

but now, python API representation generated by vppapigen
contains information about where the array length is stored.

* modifies existing response messages to use the new syntax

Change-Id: I68210bc7a3a755d03d067e9b79a567f40e2d31f3
Signed-off-by: Marek Gradzki <mgradzki@cisco.com>
diff --git a/vppapigen/node.h b/vppapigen/node.h
index 1f5a153..fc33150 100644
--- a/vppapigen/node.h
+++ b/vppapigen/node.h
@@ -73,12 +73,13 @@
     struct node_ *peer;
     struct node_ *deeper;
     int flags;
-    void *data[2];
+    void *data[3];
 } node_t;
 
 /* To shut up gcc-4.2.x warnings */
 #define CDATA0 ((char *)(this->data[0]))
 #define IDATA1 ((int)(uword)(this->data[1]))
+#define CDATA2 ((char *)(this->data[2]))
 
 #define NODE_FLAG_MANUAL_PRINT (1<<0)
 #define NODE_FLAG_MANUAL_ENDIAN (1<<1)