ipsocket.c: fix merge miss

* ext/socket/ipsocket.c (init_inetsock_internal): fix local
  variable name by merge miss.  [ruby-core:68531] [Bug #10975]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50405 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/socket/ipsocket.c

@@ -127,7 +127,7 @@ init_inetsock_internal(struct inetsock_arg *arg)
 	    port = arg->remote.serv;
 	}
 
-	rsock_syserr_fail_host_port(error, mesg, host, port);
+	rsock_syserr_fail_host_port(error, syscall, host, port);
     }
 
     arg->fd = -1;