FROMGIT: tick/broadcast: Split __tick_broadcast_oneshot_control() into a helper

In preparation for adding support for per-cpu wakeup timers, split
_tick_broadcast_oneshot_control() into a helper function which deals
only with the broadcast timer management across idle transitions.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-3-will@kernel.org



(cherry picked from commit e5007c28 tip/tip.git timers/core)
Signed-off-by: Will Deacon <willdeacon@google.com>
Bug: 185092876
Change-Id: I14c5456ec1af0b8f73c85e9571f171ea1c3c564b