Merge branch 'mneta-page_pool_get_stats'

Lorenzo Bianconi says:

====================
net: mvneta: add support for page_pool_get_stats

Introduce page_pool stats ethtool APIs in order to avoid driver duplicated
code.

Changes since v4:
- rebase on top of net-next

Changes since v3:
- get rid of wrong for loop in page_pool_ethtool_stats_get()
- add API stubs when page_pool_stats are not compiled in

Changes since v2:
- remove enum list of page_pool stats in page_pool.h
- remove leftover change in mvneta.c for ethtool_stats array allocation

Changes since v1:
- move stats accounting to page_pool code
- move stats string management to page_pool code
====================

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