cifs: Accept validate negotiate if server return NT_STATUS_NOT_SUPPORTED
Old windows version or Netapp SMB server will return
NT_STATUS_NOT_SUPPORTED since they do not allow or implement
FSCTL_VALIDATE_NEGOTIATE_INFO. The client should accept the response
provided it's properly signed.
See
https://blogs.msdn.microsoft.com/openspecification/2012/06/28/smb3-secure-dialect-negotiation/
and
MS-SMB2 validate negotiate response processing:
https://msdn.microsoft.com/en-us/library/hh880630.aspx
Samba client had already handled it.
https://bugzilla.samba.org/attachment.cgi?id=13285&action=edit
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>