Add missing structs and defines from recent SMB3.1.1 documentation

The last two updates to MS-SMB2 protocol documentation added various
flags and structs (especially relating to SMB3.1.1 tree connect).
Add missing defines and structs to smb2pdu.h

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>