Introduction of __smp barriers cleans up a bunch of duplicate code, but
it gives people an additional handle onto a "new" set of barriers - just
because they're prefixed with __* unfortunately doesn't stop anyone from
using it (as happened with other arch stuff before.)
Add a checkpatch test so it will trigger a warning.
Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Julian Calaby <julian.calaby@gmail.com> Acked-by: Joe Perches <joe@perches.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>