ARM: hisi: do not export smp_operations structures

These three structures are only defined and referenced in
mach-hisi/platsmp.c.

Drop the declarations from the header and add static qualifier
to the definitions.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wei Xu <xuwei5@hisilicon.com>