net: remove ethernet packing and set two-byte alignment

net: remove ethernet packing and set two-byte alignment

The ether header does not need to be packed since that makes no sense for
structures with only bytes in them, but it should be aligned to a two-byte
boundary to simplify access to it from code. Other packed structures that
use this also need to be updated to take account of the change, either by
removing packing - where it is clearly unneeded - or by explicitly giving
those structures 2-byte alignment also.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>