x86, hash: Simplify switch, add __init annotation

Minor cleanups:

- simplify switch statement
- add __init annotation to setup_arch_fast_hash()

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/530F09CE020000780011FBEF@nat28.tlf.novell.com


Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Thomas Graf <tgraf@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>