xfrm: add xfrm support

Signed-off-by: Sruthi Yellamraju <ysruthi@gmail.com>
Signed-off-by: Thomas Haller <thaller@redhat.com>
xfrm: style-fixes

Signed-off-by: Thomas Haller <thaller@redhat.com>
Merge branch 'xfrm'

http://lists.infradead.org/pipermail/libnl/2014-June/001503.html

Signed-off-by: Thomas Haller <thaller@redhat.com>