Merge branch 'net-Add-route-offload-indication'

Ido Schimmel says:

====================
net: Add route offload indication

This patch set adds offload indication to IPv4 and IPv6 routes. So far
offload indication was only available for the nexthop via
'RTNH_F_OFFLOAD', which is problematic as a nexthop is usually shared
between multiple routes.

Based on feedback from Roopa and David on the RFC [1], the indication is
split to 'offload' and 'trap'. This is done because not all the routes
present in hardware actually offload traffic from the kernel. For
example, host routes merely trap packets to the kernel. The two flags
are dumped to user space via the 'rtm_flags' field in the ancillary
header of the rtnetlink message.

In addition, the patch set uses the new flags in order to test the FIB
offload API by adding a dummy FIB offload implementation to netdevsim.
The new tests are added to a shared library and can be therefore shared
between different drivers.

Patches #1-#3 add offload indication to IPv4 routes.
Patches #4 adds offload indication to IPv6 routes.
Patches #5-#6 add support for the offload indication in mlxsw.
Patch #7 adds dummy FIB offload implementation in netdevsim.
Patches #8-#10 add selftests.

v2 (feedback from David Ahern):
* Patch #2: Name last argument of fib_dump_info()
* Patch #2: Move 'struct fib_rt_info' to include/net/ip_fib.h so that it
  could later be passed to fib_alias_hw_flags_set()
* Patch #3: Make use of 'struct fib_rt_info' in fib_alias_hw_flags_set()
* Patch #6: Convert to new fib_alias_hw_flags_set() interface
* Patch #7: Convert to new fib_alias_hw_flags_set() interface

[1] https://patchwork.ozlabs.org/cover/1170530/
====================

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