Merge branch 'netns-next'

Nicolas Dichtel says:

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netns: enhance netlink interface for nsid

The first patch is a small cleanup. The second patch implements notifications
for netns id events. And the last one allows to dump existing netns id from
userland.

iproute2 patches are available, I can send them on demand.

v2: drop the first patch (the fix is now in net-next)
====================

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