Merge branch 'bnxt_en-ptp'

Michael Chan says:

====================
bnxt_en: Add hardware PTP timestamping support on 575XX devices

Add PTP RX and TX hardware timestamp support on 575XX devices.  These
devices use the two-step method to implement the IEEE-1588 timestamping
support.

v2: Add spinlock to serialize access to the timecounter.
    Use .do_aux_work() for the periodic timer reading and to get the TX
    timestamp from the firmware.
    Propagate error code from ptp_clock_register().
    Make the 64-bit timer access safe on 32-bit CPUs.
    Read PHC using direct register access.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>