ptp: ocp: Separate the init and info logic

On startup, parts of the FPGA need to be initialized - break these
out into their own functions, separate from the purely informational
blocks.

On startup, distrbute the UTC:TAI offset from the NMEA GNSS parser,
if it is available.

Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>