smb3: check for and properly advertise directory lease support

smb3: check for and properly advertise directory lease support

commit f801568332321e2b1e7a8bd26c3e4913a312a2ec upstream.

Although servers will typically ignore unsupported features,
we should advertise the support for directory leases (as
Windows e.g. does) in the negotiate protocol capabilities we
pass to the server, and should check for the server capability
(CAP_DIRECTORY_LEASING) before sending a lease request for an
open of a directory.  This will prevent us from accidentally
sending directory leases to SMB2.1 or SMB2 server for example.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>