Python API: Add support for shared memory prefix

Recheck.
This is to support multiple VPP instances on same host.

Change-Id: Ibe511b1f790fc8771900085577423f7e71dc45df
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/vpp-api/python/pneum/test_pneum.c b/vpp-api/python/pneum/test_pneum.c
index b313195..20c29a7 100644
--- a/vpp-api/python/pneum/test_pneum.c
+++ b/vpp-api/python/pneum/test_pneum.c
@@ -76,7 +76,7 @@
   vl_api_show_version_t message;
   vl_api_show_version_t *mp;
   int async = 1;
-  int rv = pneum_connect("pneum_client");
+  int rv = pneum_connect("pneum_client", NULL);
 
   if (rv != 0) {
     printf("Connect failed: %d\n", rv);