Maximum packet size is 10000 (RIST_MAX_PACKET_SIZE, which is unfortunately
private) minus the RIST protocol overhead which is 28 bytes for the unencrypted
case, 36 for the encrypted case.
Signed-off-by: Marton Balint <cus@passwd.hu>
Queue tracking makes no difference so remove it, return EAGAIN of no data is
available and rist data block needs to be freed even for zero sized packets.
Signed-off-by: Marton Balint <cus@passwd.hu>