ice: support Rx timestamp on flex descriptor

ice: support Rx timestamp on flex descriptor

To support Rx timestamp offload, VIRTCHNL_OP_1588_PTP_CAPS is sent by
the VF to request PTP capability and responded by the PF what capability
is enabled for that VF.

Hardware captures timestamps which contain only 32 bits of nominal
nanoseconds, as opposed to the 64bit timestamps that the stack expects.
To convert 32b to 64b, we need a current PHC time.
VIRTCHNL_OP_1588_PTP_GET_TIME is sent by the VF and responded by the
PF with the current PHC time.

Signed-off-by: Simei Su <simei.su@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Co-developed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Signed-off-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>