ptp: ocp: Program the signal generators via PTP_CLK_REQ_PEROUT

The signal generators can be programmed either via the sysfs
file or through a PTP_CLK_REQ_PEROUT ioctl request.

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