i40e: Fix for 10G ports LED not blinking

On some hardware LEDs would not blink after command 'ethtool -p {eth-port}'
in certain circumstances. Now, function does not care about the activity
of the LED (though still preserves its state) but forcibly executes
identification blinking and then restores the LED state.

Signed-off-by: Piotr Marczak <piotr.marczak@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>