Fix compile error.

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@579 7dcaeef0-15fb-0310-b436-a5af3365683c

libssh/sftp.c

@@ -384,7 +384,7 @@ static int sftp_read_and_dispatch(SFTP_SESSION *sftp) {
 
   msg = sftp_get_message(packet);
   sftp_packet_free(packet);
-  if (message == NULL) {
+  if (msg == NULL) {
     sftp_leave_function();
     return -1;
   }