cpumask: convert struct clock_event_device to cpumask pointers.
Impact: change calling convention of existing clock_event APIs struct clock_event_timer's cpumask field gets changed to take pointer, as does the ->broadcast function. Another single-patch change. For safety, we BUG_ON() in clockevents_register_device() if it's not set. Signed-off-by: Rusty Russell <email@example.com> Cc: Ingo Molnar <firstname.lastname@example.org>