cifs: protect session status check in smb2_reconnect()

commit 5bff9f74 upstream.

Use @ses->ses_lock to protect access of @ses->ses_status.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>