Merge branch 'fib-merge-nl-policies'

Florian Westphal says:

====================
fib: merge nl policies

v4: resend with fixed subject line.  I preserved review tags
    from David Ahern.
v3: drop first two patches, otherwise unchanged.

This series merges the different (largely identical) nla policies.

v2 also squashed the ->suppress() implementation, I've dropped this.
Problem is that it needs ugly ifdef'ry to avoid build breakage
with CONFIG_INET=n || IPV6=n.

Given that even microbenchmark doesn't show any noticeable improvement
when ->suppress is inlined (it uses INDIRECT_CALLABLE) i decided to toss
the patch instead of adding more ifdefs.
====================

Link: https://lore.kernel.org/r/20211216120507.3299-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>