igb: Remove redundant runtime resume for ethtool_ops

igb: Remove redundant runtime resume for ethtool_ops

749ab2cd1270 ("igb: add basic runtime PM support") added
ethtool_ops.begin() and .complete(), which used pm_runtime_get_sync() to
resume suspended devices before any ethtool_ops callback and allow suspend
after it completed.

Subsequently, f32a21376573 ("ethtool: runtime-resume netdev parent before
ethtool ioctl ops") added pm_runtime_get_sync() in the dev_ethtool() path,
so the device is resumed before any ethtool_ops callback even if the driver
didn't supply a .begin() callback.

Remove the .begin() and .complete() callbacks, which are now redundant
because dev_ethtool() already resumes the device.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>