[SPARC64]: Add needed pm_power_off symbol.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/power.c

@@ -14,6 +14,7 @@
 #include <linux/signal.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
+#include <linux/pm.h>
 
 #include <asm/system.h>
 #include <asm/ebus.h>
@@ -70,6 +71,9 @@ void machine_power_off(void)
 	machine_halt();
 }
 
+void (*pm_power_off)(void) = machine_power_off;
+EXPORT_SYMBOL(pm_power_off);
+
 #ifdef CONFIG_PCI
 static int powerd(void *__unused)
 {