cpuidle: Fix poll_idle() noinstr annotation

The instrumentation_begin()/end() annotations in poll_idle() were
complete nonsense. Specifically they caused tracing to happen in the
middle of noinstr code, resulting in RCU splats.

Now that local_clock() is noinstr, mark up the rest and let it rip.

Fixes: 00717eb8 ("cpuidle: Annotate poll_idle()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/oe-lkp/202301192148.58ece903-oliver.sang@intel.com
Link: https://lore.kernel.org/r/20230126151323.819534689@infradead.org