Merge branch 'ipv4-convert-several-tos-fields-to-dscp_t'

Guillaume Nault says:

====================
ipv4: Convert several tos fields to dscp_t

Continue the work started with commit a410a0cf9885 ("ipv6: Define
dscp_t and stop taking ECN bits into account in fib6-rules") and
convert more structure fields and variables to dscp_t. This series
focuses on struct fib_rt_info, struct fib_entry_notifier_info and their
users (networking drivers).

The purpose of dscp_t is to ensure that ECN bits don't influence IP
route lookups. It does so by ensuring that dscp_t variables have the
ECN bits cleared.

Notes:
  * This series is entirely about type annotation and isn't supposed
to have any user visible effect.

  * The first two patches have to introduce a few dsfield <-> dscp
conversions in the affected drivers, but those are then removed when
converting the internal driver structures (patches 3-5). In the end,
drivers don't have to handle any conversion.
====================

Link: https://lore.kernel.org/r/cover.1649445279.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>