zebra: Fix some warnings found during compile.

This commit fixes some warnings found in Martin's Testbed
that compiles sun solaris and freebsd images.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
diff --git a/zebra/rtread_getmsg.c b/zebra/rtread_getmsg.c
index 8915394..e1ec670 100644
--- a/zebra/rtread_getmsg.c
+++ b/zebra/rtread_getmsg.c
@@ -26,6 +26,7 @@
 #include "log.h"
 #include "if.h"
 #include "vrf.h"
+#include "vty.h"
 
 #include "zebra/rib.h"
 #include "zebra/zserv.h"