sfc: support separate PTP and general timestamping

sfc: support separate PTP and general timestamping

BugLink: https://bugs.launchpad.net/bugs/1836635
Support MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2.  Extract general
 timestamp corrections in addition to PTP corrections.  Apply receive
 timestamp corrections for general datapath receive timestamping, and
 correspondingly for transmit.

Signed-off-by: Laurence Evans <levans@solarflare.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 04796f4c4dc4ac4c4f405c22e20dc9ae1068eea5)
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>