fix reused_session check

Author: chronolaw

lib/resty/core/socket.lua

@@ -266,6 +266,10 @@ local function sslhandshake(cosocket, reused_session, server_name, ssl_verify,
 
     assert(rc == FFI_OK)
 
+    if reused_session == false then
+        return true
+    end
+
     if session_ptr[0] == nil then
         return nil
     end