galois.c: fix compiler warning

galois_create_split_w8_tables() takes no parameter, remove '8' passed
to the function in one case.

osd/ErasureCodePluginJerasure/galois.c: In function 'galois_w32_region_multiply':
osd/ErasureCodePluginJerasure/galois.c:696:5: warning: call to function 'galois_create_split_w8_tables' without a real prototype [-Wunprototyped-calls]
In file included from osd/ErasureCodePluginJerasure/galois.c:53:0:
osd/ErasureCodePluginJerasure/galois.h:71:12: note: 'galois_create_split_w8_tables' was declared here

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>