ppc: Minor smp changes for consistency with ppc64

This makes platform code use the smp_ops variable directly instead
of ppc_md.smp_ops, removes the two unused `data' and `wait' arguments
from the *_message_pass() functions, and removes the call to the
never-implemented smp_ops->space_timers() function.

Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index 9416fca..7eb0c34 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -312,9 +312,9 @@
 #ifdef CONFIG_SMP
 	/* Check for Core99 */
 	if (find_devices("uni-n") || find_devices("u3"))
-		ppc_md.smp_ops = &core99_smp_ops;
+		smp_ops = &core99_smp_ops;
 	else
-		ppc_md.smp_ops = &psurge_smp_ops;
+		smp_ops = &psurge_smp_ops;
 #endif /* CONFIG_SMP */
 
 	pci_create_OF_bus_map();