ice: unify logic for programming PFINT_TSYN_MSK

Commit d938a8cc ("ice: Auxbus devices & driver for E822 TS") modified
how Tx timestamps are handled for E822 devices. On these devices, only the
clock owner handles reading the Tx timestamp data from firmware. To do
this, the PFINT_TSYN_MSK register is modified from the default value to one
which enables reacting to a Tx timestamp on all PHY ports.

The driver currently programs PFINT_TSYN_MSK in different places depending
on whether the port is the clock owner or not. For the clock owner, the
PFINT_TSYN_MSK value is programmed during ice_ptp_init_owner just before
calling ice_ptp_tx_ena_intr to program the PHY ports.

For the non-clock owner ports, the PFINT_TSYN_MSK is programmed during
ice_ptp_init_port.

If a large enough device reset occurs, the PFINT_TSYN_MSK register will be
reset to the default value in which only the PHY associated directly with
the PF will cause the Tx timestamp interrupt to trigger.

The driver lacks logic to reprogram the PFINT_TSYN_MSK register after a
device reset. For the E822 device, this results in the PF no longer
responding to interrupts for other ports. This results in failure to
deliver Tx timestamps to user space applications.

Rename ice_ptp_configure_tx_tstamp to ice_ptp_cfg_tx_interrupt, and unify
the logic for programming PFINT_TSYN_MSK and PFINT_OICR_ENA into one place.
This function will program both registers according to the combination of
user configuration and device requirements.

This ensures that PFINT_TSYN_MSK is always restored when we configure the
Tx timestamp interrupt.

Fixes: d938a8cc

 ("ice: Auxbus devices & driver for E822 TS")
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>