mlx4_en_init_timestamp was called before creation of netdev and port
init, thus used uninitialized values.  Specifically - NIC frequency was
incorrect causing wrong calculations and later wrong HW timestamps.

Fixes: 1ec4864b ('net/mlx4_en: Fixed crash when port type is changed')
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: NMarina Varshaver <marinav@mellanox.com>
Signed-off-by: NEran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>