PM / wakeirq: Add wakeup name to dedicated wake irqs

This makes it easy to grep :wakeup /proc/interrupts.

Suggested-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>