[POWERPC] Fix undefined pmu_sys_suspended compilation error

pmu_sys_suspended is declared extern when:
	defined(CONFIG_PM_SLEEP) && defined(CONFIG_PPC32)
but only defined when:
	defined(CONFIG_SUSPEND) && defined(CONFIG_PPC32)
which is wrong.  Let's fix that.
Signed-off-by: NTony Breeds <tony@bakeyournoodle.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

include/linux/pmu.h

@@ -192,7 +192,7 @@ extern unsigned int pmu_power_flags;
 extern void pmu_backlight_init(void);
 
 /* some code needs to know if the PMU was suspended for hibernation */
-#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_PPC32)
+#if defined(CONFIG_SUSPEND) && defined(CONFIG_PPC32)
 extern int pmu_sys_suspended;
 #else
 /* if power management is not configured it can't be suspended */