Merge branch 'net_get_random_once'

Hannes Frederic Sowa says:

====================
This series implements support for delaying the initialization of secret
keys, e.g. used for hashing, for as long as possible. This functionality
is implemented by a new macro, net_get_random_bytes.

I already used it to protect the socket hashes, the syncookie secret
(most important) and the tcp_fastopen secrets.

Changelog:
v2) Use static_keys in net_get_random_once to have as minimal impact to
    the fast-path as possible.
v3) added patch "static_key: WARN on usage before jump_label_init was called":
    Patch "x86/jump_label: expect default_nop if static_key gets enabled
    on boot-up" relaxes the checks for using static_key primitives before
    jump_label_init. So tighten them first.
v4) Update changelog on the patch "static_key: WARN on usage before
    jump_label_init was called"

Included patches:
 ipv4: split inet_ehashfn to hash functions per compilation unit
 ipv6: split inet6_ehashfn to hash functions per compilation unit
 static_key: WARN on usage before jump_label_init was called
 x86/jump_label: expect default_nop if static_key gets enabled on boot-up
 net: introduce new macro net_get_random_once
 inet: split syncookie keys for ipv4 and ipv6 and initialize with net_get_random_once
 inet: convert inet_ehash_secret and ipv6_hash_secret to net_get_random_once
 tcp: switch tcp_fastopen key generation to net_get_random_once
 net: switch net_secret key generation to net_get_random_once
====================

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