On session close, the IPC is closed and the server must release all
tcons of the session. It doesn't matter if we send a ipc close or
not.
Besides, it will make the server to not close durable and resilient
files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
SMB2 LOGOFF Request.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>