staging: skein: fix sparse warning for static arrays

This patch fixes the following sparse warnings:

skein_iv.h:23:11: warning: symbol 'SKEIN_256_IV_128' was not declared. Should it be static?
skein_iv.h:31:11: warning: symbol 'SKEIN_256_IV_160' was not declared. Should it be static?
skein_iv.h:39:11: warning: symbol 'SKEIN_256_IV_224' was not declared. Should it be static?
skein_iv.h:47:11: warning: symbol 'SKEIN_256_IV_256' was not declared. Should it be static?
skein_iv.h:55:11: warning: symbol 'SKEIN_512_IV_128' was not declared. Should it be static?
skein_iv.h:67:11: warning: symbol 'SKEIN_512_IV_160' was not declared. Should it be static?
skein_iv.h:79:11: warning: symbol 'SKEIN_512_IV_224' was not declared. Should it be static?
skein_iv.h:91:11: warning: symbol 'SKEIN_512_IV_256' was not declared. Should it be static?
skein_iv.h:103:11: warning: symbol 'SKEIN_512_IV_384' was not declared. Should it be static?
skein_iv.h:115:11: warning: symbol 'SKEIN_512_IV_512' was not declared. Should it be static?
skein_iv.h:127:11: warning: symbol 'SKEIN_1024_IV_384' was not declared. Should it be static?
skein_iv.h:147:11: warning: symbol 'SKEIN_1024_IV_512' was not declared. Should it be static?
skein_iv.h:167:11: warning: symbol 'SKEIN_1024_IV_1024' was not declared. Should it be static?

by declaring the initialization vectors in question as static.  The header
skein_iv.h is only included by skein.c

Signed-off-by: James A Shackleford <shack@linux.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>