cpufreq: Remove the ->stop_cpu() driver callback

Now that all users of ->stop_cpu() have been migrated to using other
callbacks, drop it from the core.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Minor edits in the subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Documentation/cpu-freq/cpu-drivers.rst

@@ -71,9 +71,6 @@ And optionally
  .exit - A pointer to a per-policy cleanup function called during
  CPU_POST_DEAD phase of cpu hotplug process.
 
- .stop_cpu - A pointer to a per-policy stop function called during
- CPU_DOWN_PREPARE phase of cpu hotplug process.
-
  .suspend - A pointer to a per-policy suspend function which is called
  with interrupts disabled and _after_ the governor is stopped for the
  policy.

Documentation/translations/zh_CN/cpu-freq/cpu-drivers.rst

@@ -76,9 +76,6 @@ CPUfreq核心层注册一个cpufreq_driver结构体。
  .exit - 一个指向per-policy清理函数的指针，该函数在cpu热插拔过程的CPU_POST_DEAD
  阶段被调用。
 
- .stop_cpu - 一个指向per-policy停止函数的指针，该函数在cpu热插拔过程的CPU_DOWN_PREPARE
- 阶段被调用。
-
  .suspend - 一个指向per-policy暂停函数的指针，该函数在关中断且在该策略的调节器停止
  后被调用。
 

drivers/cpufreq/cpufreq.c

@@ -1606,9 +1606,6 @@ static int cpufreq_offline(unsigned int cpu)
 		policy->cdev = NULL;
 	}
 
-	if (cpufreq_driver->stop_cpu)
-		cpufreq_driver->stop_cpu(policy);
-
 	if (has_target())
 		cpufreq_exit_governor(policy);
 

include/linux/cpufreq.h

@@ -371,7 +371,6 @@ struct cpufreq_driver {
 	int		(*online)(struct cpufreq_policy *policy);
 	int		(*offline)(struct cpufreq_policy *policy);
 	int		(*exit)(struct cpufreq_policy *policy);
-	void		(*stop_cpu)(struct cpufreq_policy *policy);
 	int		(*suspend)(struct cpufreq_policy *policy);
 	int		(*resume)(struct cpufreq_policy *policy);