ksmbd: reduce server smbdirect max send/receive segment sizes

Reduce ksmbd smbdirect max segment send and receive size to 1364
to match protocol norms. Larger buffers are unnecessary and add
significant memory overhead.

Signed-off-by: Tom Talpey <tom@talpey.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>