smb: client: remove unused smbd_connection.count_reassembly_queue

smb: client: remove unused smbd_connection.count_reassembly_queue

This basically represents the same information as
sc->recv_io.reassembly.queue_length.

The only thing that's different is that
smbd_connection.count_reassembly_queue was updated in each
loop step, while sc->recv_io.reassembly.queue_length is only
updated once after the loop in smbd_recv.
Also sc->recv_io.reassembly.queue_length is updated under
a spinlock.

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