Merge branch 'kill_arch_fast_hash'

Daniel Borkmann says:

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Kill arch_fast_hash

Due to the size of changes I have based this against net-next,
also given 3.18 is already out. I've split this into 3 parts,
the first two to remove existing users (so they can optionally
go to stable) and the last one to kill the remaining library bits.

Let me know if there are any issues.
====================

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