smb: server: let smb_direct_flush_send_list() invalidate a remote key first

[ Upstream commit 1b534263 ]

If we want to invalidate a remote key we should do that as soon as
possible, so do it in the first send work request.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>