net/mlx5: Query PPS pin operational status before registering it

In a special configuration, a ConnectX6-Dx pin pps-out might be activated
when driver is loaded. Fix the driver to always read the operational pin
mode when registering it, and advertise it accordingly.

Fixes: ee7f1220

 ("net/mlx5e: Implement 1PPS support")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>