Merge branch 'am65-cpsw-ethtool-mac-stats'

Roger Quadros says:

===================
net: eth: am65-cpsw: add ethtool MAC stats

Gets 'ethtool -S eth0 --groups eth-mac' command to work.

Also set default TX channels to maximum available and does
cleanup in am65_cpsw_nuss_common_open() error path.

Changelog:
v2:
- add __iomem to *stats, to prevent sparse warning
- clean up RX descriptors and free up SKB in error handling of
  am65_cpsw_nuss_common_open()
- Re-arrange some funcitons to avoid forward declaration
====================

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