Add counting of tx and rx PTP packets.
__recv_and_count and __send_and_log are arch independent functions.
Increase WRS_PPSI_SHMEM_VERSION due to add of tx_count and tx_count firlds in
pp_instance.
Update WRS_PPSI_SHMEM_VERSION to 5
Signed-off-by: Adam Wujek <adam.wujek@cern.ch>