ibmvnic: Feature implementation of Vital Product Data (VPD) for the ibmvnic driver

This patch implements and enables VDP support for the ibmvnic driver.
Moreover, it includes the implementation of suitable structs, signal
 transmission/handling and functions which allows the retrival of firmware
 information from the ibmvnic card through the ethtool command.

Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com>
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>