api: keep AddressSanitizer happy

Type: fix

Change-Id: I793206068b8dca15b2f7f525ae1049139333c5b8
Signed-off-by: Benoît Ganne <bganne@cisco.com>
diff --git a/src/vlibapi/api_shared.c b/src/vlibapi/api_shared.c
index bf03751..0ea5280 100644
--- a/src/vlibapi/api_shared.c
+++ b/src/vlibapi/api_shared.c
@@ -813,6 +813,7 @@
 
   while (!svm_queue_sub (q, (u8 *) &msg, SVM_Q_WAIT, 0))
     {
+      VL_MSG_API_UNPOISON ((u8 *) msg);
       msgbuf_t *msgbuf = (msgbuf_t *) ((u8 *) msg - offsetof (msgbuf_t, data));
       vl_msg_api_handler ((void *) msg, ntohl (msgbuf->data_len));
     }