Merge branch 'enetc-Support-extended-BD-rings-at-runtime'

Merge branch 'enetc-Support-extended-BD-rings-at-runtime'

Claudiu Manoil says:

====================
enetc: Support extended BD rings at runtime

First two patches are just misc code cleanup.
The 3rd patch prepares the Rx BD processing code to be extended
to processing both normal and extended BDs.
The last one adds extended Rx BD support for timestamping
without the need of a static config. Finally, the config option
FSL_ENETC_HW_TIMESTAMPING can be dropped.
Care was taken not to impact non-timestamping usecases.
====================

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