net: cavium: Register driver with PCI subsys IDs

Across Cavium's ThunderX and Marvell's OcteonTx2 silicons
the PTP timestamping block's PCI device ID and vendor ID
have remained same but the HW architecture has changed.

Hence added PCI subsystem IDs to the device table to avoid
this driver from being probed on OcteonTx2 silicons.

Signed-off-by: Prakash Brahmajyosyula <bprakash@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>