Merge branch 'ipv4-convert-ip_route_input_slow-and-its-callers-to-dscp_t'

Guillaume Nault says:

====================
ipv4: Convert ip_route_input_slow() and its callers to dscp_t.

Prepare ip_route_input_slow() and its call chain to future conversion
of ->flowi4_tos.

The ->flowi4_tos field of "struct flowi4" is used in many different
places, which makes it hard to convert it from __u8 to dscp_t.

In order to avoid a big patch updating all its users at once, this
patch series gradually converts some users to dscp_t. Those users now
set ->flowi4_tos from a dscp_t variable that is converted to __u8 using
inet_dscp_to_dsfield().

When all users of ->flowi4_tos will use a dscp_t variable, converting
that field to dscp_t will just be a matter of removing all the
inet_dscp_to_dsfield() conversions.

This series concentrates on ip_route_input_slow() and its direct and
indirect callers.
====================

Link: https://patch.msgid.link/cover.1727807926.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>