cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases

PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both
should be called or both shouldn't be.

In case we have started PRECHANGE notifier and found an error, we must call
POSTCHANGE notifier with freqs.new = freqs.old to guarantee that sequence of
calling notifiers is complete.

This patch fixes it.

This also removes code setting policy->cur as this is also done by POSTCHANGE
notifier.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/arm_big_little.c

@@ -84,11 +84,9 @@ static int bL_cpufreq_set_target(struct cpufreq_policy *policy,
 	ret = clk_set_rate(clk[cur_cluster], freqs.new * 1000);
 	if (ret) {
 		pr_err("clk_set_rate failed: %d\n", ret);
-		return ret;
+		freqs.new = freqs.old;
 	}
 
-	policy->cur = freqs.new;
-
 	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
 
 	return ret;