cpufreq: Do not allow ->setpolicy drivers to provide ->target

cpufreq drivers that provide the ->setpolicy() callback are supposed
to have integrated governors, so they don't need to set ->target()
or ->target_index() and may confuse the core if any of these callbacks
is present.

For this reason, add a check preventing ->setpolicy cpufreq drivers
from registering if they have non-NULL ->target or ->target_index.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/cpufreq.c

@@ -2299,7 +2299,9 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 
 	if (!driver_data || !driver_data->verify || !driver_data->init ||
 	    !(driver_data->setpolicy || driver_data->target_index ||
-		    driver_data->target))
+		    driver_data->target) ||
+	     (driver_data->setpolicy && (driver_data->target_index ||
+		    driver_data->target)))
 		return -EINVAL;
 
 	pr_debug("trying to register driver %s\n", driver_data->name);