sftpserver: Free memory on error condition

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <norbertpocs0@gmail.com>
(cherry picked from commit 69c169e4cb)

src/sftpserver.c

@@ -1112,6 +1112,7 @@ process_opendir(sftp_client_message client_msg)
         sftp_reply_handle(client_msg, handle_s);
         ssh_string_free(handle_s);
     } else {
+        free(h);
         closedir(dir);
         sftp_reply_status(client_msg, SSH_FX_FAILURE, "No handle available");
     }