igc: Use netdev log helpers in igc_dump.c

In igc_dump.c we print log messages using dev_* and pr_* helpers,
generating inconsistent output with the rest of the driver. Since this
is a network device driver, we should preferably use netdev_* helpers
because they append the interface name to the message, helping making
sense out of the logs.

This patch converts all dev_* and pr_* calls to netdev_*.

Quick note about igc_rings_dump(): This function is always called with
valid adapter->netdev so there is not need to check it.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>