security: Fix some typos and potential NULL-deref

This patch against the git tree fixes minor typos, some of them possibily
leading to NULL-pointer dereference in rare conditions.

Signed-off-by: Remi Gacogne <rgacogne-github@coredump.fr>
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Acked-by: Feng Lu <lu.feng@6wind.com>
diff --git a/lib/vty.c b/lib/vty.c
index 0d6345c..96cb1e4 100644
--- a/lib/vty.c
+++ b/lib/vty.c
@@ -1856,9 +1856,11 @@
     {
       case AF_INET:
         naddr=&su.sin.sin_addr;
+        break;
 #ifdef HAVE_IPV6
       case AF_INET6:
         naddr=&su.sin6.sin6_addr;
+        break;
 #endif	
     }