[POWERPC] cell: Move SPU affinity init to spu_management_of_ops

[POWERPC] cell: Move SPU affinity init to spu_management_of_ops

This patch moves affinity initialization code from spu_base.c to a
new spu_management_of_ops function (init_affinity), which is empty
in the case of PS3. This fixes a linking problem that was happening
when compiling for PS3.
Also, some small code style changes were made.

Signed-off-by: Andre Detsch <[email protected]>
Signed-off-by: Geoff Levand <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>