Merge branch 'skbuff-struct-group'

Kees Cook says:

====================
skbuff: Switch structure bounds to struct_group()

This is a pair of patches to add struct_group() to struct sk_buff. The
first is needed to work around sparse-specific complaints, and is new
for v2. The second patch is the same as originally sent as v1.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>