ptp_qoriq: fix register memory map

The 1588 timer on eTSEC Ethernet controller uses different
register memory map with DPAA Ethernet controller.
Now the new ENETC Ethernet controller uses same reigster
memory map with DPAA. To support ENETC, let's use register
memory map of DPAA/ENETC in default.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>