iavf: Add trace while removing device

Add kernel trace that device was removed.
Currently there is no such information.
I.e. Host admin removes a PCI device from a VM,
than on VM shall be info about the event.

This patch adds info log to iavf_remove function.

Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>