cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory

When we don't have any file in cpu/cpufreq directory we shouldn't
create it. Specially with the introduction of per-policy governor
instance patchset, even governors are moved to
cpu/cpu*/cpufreq/governor-name directory and so this directory is
just not required.

Lets have it only when required.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index fbf392a..1b5b5ef 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -71,6 +71,10 @@
 
 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */
 extern struct kobject *cpufreq_global_kobject;
+int cpufreq_get_global_kobject(void);
+void cpufreq_put_global_kobject(void);
+int cpufreq_sysfs_create_file(const struct attribute *attr);
+void cpufreq_sysfs_remove_file(const struct attribute *attr);
 
 #define CPUFREQ_ETERNAL			(-1)
 struct cpufreq_cpuinfo {