cpufreq: move freq change notifications to cpufreq core

Most of the drivers do following in their ->target_index() routines:

	struct cpufreq_freqs freqs;
	freqs.old = old freq...
	freqs.new = new freq...

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);

	/* Change rate here */

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);

This is replicated over all cpufreq drivers today and there doesn't exists a
good enough reason why this shouldn't be moved to cpufreq core instead.

There are few special cases though, like exynos5440, which doesn't do everything
on the call to ->target_index() routine and call some kind of bottom halves for
doing this work, work/tasklet/etc..

They may continue doing notification from their own code as flag:
CPUFREQ_ASYNC_NOTIFICATION is already set for them.

All drivers are also modified in this patch to avoid breaking 'git bisect', as
double notification would happen otherwise.

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/ia64-acpi-cpufreq.c

@@ -141,7 +141,6 @@ processor_set_freq (
 {
 	int			ret = 0;
 	u32			value = 0;
-	struct cpufreq_freqs    cpufreq_freqs;
 	cpumask_t		saved_mask;
 	int			retval;
 
@@ -168,13 +167,6 @@ processor_set_freq (
 	pr_debug("Transitioning from P%d to P%d\n",
 		data->acpi_data.state, state);
 
-	/* cpufreq frequency struct */
-	cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency;
-	cpufreq_freqs.new = data->freq_table[state].frequency;
-
-	/* notify cpufreq */
-	cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_PRECHANGE);
-
 	/*
 	 * First we write the target state's 'control' value to the
 	 * control_register.
@@ -186,22 +178,11 @@ processor_set_freq (
 
 	ret = processor_set_pstate(value);
 	if (ret) {
-		unsigned int tmp = cpufreq_freqs.new;
-		cpufreq_notify_transition(policy, &cpufreq_freqs,
-				CPUFREQ_POSTCHANGE);
-		cpufreq_freqs.new = cpufreq_freqs.old;
-		cpufreq_freqs.old = tmp;
-		cpufreq_notify_transition(policy, &cpufreq_freqs,
-				CPUFREQ_PRECHANGE);
-		cpufreq_notify_transition(policy, &cpufreq_freqs,
-				CPUFREQ_POSTCHANGE);
 		printk(KERN_WARNING "Transition failed with error %d\n", ret);
 		retval = -ENODEV;
 		goto migrate_end;
 	}
 
-	cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_POSTCHANGE);
-
 	data->acpi_data.state = state;
 
 	retval = 0;