be2net: fix to dynamically generate MAC Address for VFs

The BE ASIC/firmware doesnot reserve and assign MAC address for VFs.
This results in the VF interfaces being created with MAC Address 0.
The code change proposed takes the MAC address of PF to generate a seed.
MAC Address for VFs are assigned incrementally starting from the seed.
These addresses are programmed in the ASIC by the PF and the VF driver
queries for the MAC address during its probe.

Signed-off-by: Ajit Khaparde <ajitk@serverengines.com>
Signed-off-by: David S. Miller <davem@davemloft.net>