parisc: Mark cr16 clocksource unstable on SMP systems

The cr16 interval timer of each CPU is not syncronized to other cr16 timers in other CPUs in a SMP system. So, delay the registration of the cr16 clocksource until all CPUs have been detected and then mark it as unstable and lower it's rating before registering it at the clockource framework.

This patch fixes the stalled CPU warnings which we have seen since introduction of the cr16 clocksource.

index 325f30d..47ef8fd 100644
@@ -289,9 +289,26 @@ void __init time_init(void)
 
 	cr16_hz = 100 * PAGE0->mem_10msec;  /* Hz */
 
-	/* register at clocksource framework */
-	clocksource_register_hz(&clocksource_cr16, cr16_hz);