Merge branch 'bpf-persistent'

Daniel Borkmann says:

====================
BPF updates

This set adds support for persistent maps/progs. Please see
individual patches for further details. A man-page update
to bpf(2) will be sent later on, also a iproute2 patch for
support in tc.

v1 -> v2:
  - Reworked most of patch 4 and 5
  - Rebased to latest net-next
====================

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