fs/cifs: correctly to anonymous authentication for the NTLM(v1) authentication

fs/cifs: correctly to anonymous authentication for the NTLM(v1) authentication

[ Upstream commit 777f69b8d26bf35ade4a76b08f203c11e048365d ]

Only server which map unknown users to guest will allow
access using a non-null NTChallengeResponse.

For Samba it's the "map to guest = bad user" option.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913

Signed-off-by: Stefan Metzmacher <metze@samba.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>