rpcrt4: Fix a typo in rpcrt4_ip_tcp_open that would cause the function
to go into an infinite loop if getaddrinfo returned more than one entry.

dlls/rpcrt4/rpc_transport.c

diff --git a/dlls/rpcrt4/rpc_transport.c b/dlls/rpcrt4/rpc_transport.c
index 2f65f75..d50b60b 100644
--- a/dlls/rpcrt4/rpc_transport.c
+++ b/dlls/rpcrt4/rpc_transport.c
@@ -600,7 +600,7 @@
     return RPC_S_SERVER_UNAVAILABLE;
   }
 
-  for (ai_cur = ai; ai_cur; ai_cur = ai->ai_next)
+  for (ai_cur = ai; ai_cur; ai_cur = ai_cur->ai_next)
   {
     if (TRACE_ON(rpc))
     {