net: tcp2: Update the sequence compare on peer resend

In order to handle sequence overflow cases, use
net_tcp_seq_greater() to check if the sequence is greater/lower.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>