vmxnet3: prepare for version 3 changes

vmxnet3: prepare for version 3 changes

Orabug: 25639933

vmxnet3 is currently at version 2, but some command definitions from
previous vmxnet3 versions are missing. Add those definitions before
moving to version 3.

Also, introduce utility macros for vmxnet3 version comparison and update
Copyright information and Maintained by.

Signed-off-by: Shrikrishna Khare <skhare@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 190af10f0b5a07140ec4ce8e6ef04b7cb238dde1)
Signed-off-by: Brian Maly <brian.maly@oracle.com>