perf/x86/amd/power: Change hotplug notifier to a symmetric structure

To simplify the hotplug mechanism move the starting callback to
online. There is no functional requirement that the cpumask bit has to
be set in the starting callback.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153334.944849172@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/events/amd/power.c

@@ -255,7 +255,7 @@ static void power_cpu_init(int cpu)
 	 * 1) If any CPU is set at cpu_mask in the same compute unit, do
 	 * nothing.
 	 * 2) If no CPU is set at cpu_mask in the same compute unit,
-	 * set current STARTING CPU.
+	 * set current ONLINE CPU.
 	 *
 	 * Note: if there is a CPU aside of the new one already in the
 	 * sibling mask, then it is also in cpu_mask.
@@ -272,7 +272,7 @@ power_cpu_notifier(struct notifier_block *self, unsigned long action, void *hcpu
 
 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_DOWN_FAILED:
-	case CPU_STARTING:
+	case CPU_ONLINE:
 		power_cpu_init(cpu);
 		break;
 	case CPU_DOWN_PREPARE: