Merge branch 'nexthop-Small-changes'

Ido Schimmel says:

====================
nexthop: Small changes

This patch set contains a few small changes that I split out of the RFC
I sent last week [1]. Main change is the conversion of the nexthop
notification chain to a blocking chain so that it could be reused by
device drivers for nexthop objects programming in the future.

Tested with fib_nexthops.sh:

Tests passed: 164
Tests failed:   0

[1] https://lore.kernel.org/netdev/20200908091037.2709823-1-idosch@idosch.org/
====================

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