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/vpp-api/java/jvpp/gen/jvpp_gen.py b/vpp-api/java/jvpp/gen/jvpp_gen.py
index c08593e..26bcea1 100755
--- a/vpp-api/java/jvpp/gen/jvpp_gen.py
+++ b/vpp-api/java/jvpp/gen/jvpp_gen.py
@@ -80,11 +80,15 @@
         if len(i) is 3:  # array type
             types_list.append(vpp_2_jni_type_mapping[i[0]] + 'Array')
             c_types_list.append(i[0] + '[]')
-            lengths_list.append(i[2])
+            lengths_list.append((i[2], False))
+        elif len(i) is 4:  # variable length array type
+            types_list.append(vpp_2_jni_type_mapping[i[0]] + 'Array')
+            c_types_list.append(i[0] + '[]')
+            lengths_list.append((i[3], True))
         else:  # primitive type
             types_list.append(vpp_2_jni_type_mapping[i[0]])
             c_types_list.append(i[0])
-            lengths_list.append(0)
+            lengths_list.append((0, False))
     return types_list, c_types_list, lengths_list