powerpc: Use common cpu_die (fixes SMP+SUSPEND build)

Configuring a powerpc 32 bit kernel for both SMP and SUSPEND turns on
CPU_HOTPLUG to enable disable_nonboot_cpus to be called by the common
suspend code.  Previously the definition of cpu_die for ppc32 was in
the powermac platform code, causing it to be undefined if that platform
as not selected.

arch/powerpc/kernel/built-in.o: In function 'cpu_idle':
arch/powerpc/kernel/idle.c:98: undefined reference to 'cpu_die'

Move the code from setup_64 to smp.c and rename the power mac
versions to their specific names.

Note that this does not setup the cpu_die pointers in either
smp_ops (request a given cpu die) or ppc_md (make this cpu die),
for other platforms but there are generic versions in smp.c.

Reported-by: Matt Sealey <matt@genesi-usa.com>
Reported-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 9143891..cea6698 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -573,12 +573,6 @@
 	printk("[boot]%04x %s\n", src, msg);
 }
 
-void cpu_die(void)
-{
-	if (ppc_md.cpu_die)
-		ppc_md.cpu_die();
-}
-
 #ifdef CONFIG_SMP
 #define PCPU_DYN_SIZE		()
 
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index bf36616..5c196d1 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -648,4 +648,10 @@
 {
 	mutex_unlock(&powerpc_cpu_hotplug_driver_mutex);
 }
+
+void cpu_die(void)
+{
+	if (ppc_md.cpu_die)
+		ppc_md.cpu_die();
+}
 #endif