Debug logs in helper functions like tcp_unsent_len() or
tcp_window_full() are not very helpful and generate a heavy, unnecessary
log output. Therefore, tcp_unsent_len() will no longer generate log, and
tcp_window_full() will print out a log only when the window is actually
full, which could be an useful information.
Also, reduce the log load during TX, as currently redundant logs were
printed in tcp_out_ext(), tcp_send_process_no_lock() and finally in
tcp_send().
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
cb0a12311b