cpufreq: Use signed type for 'ret' variable, to store negative error values

There are places where the variable 'ret' is declared as unsigned int
and then used to store negative return values such as -EINVAL. Fix them
by declaring the variable as a signed quantity.
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/cpufreq.c

@@ -437,7 +437,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *policy,
 static ssize_t store_##file_name					\
 (struct cpufreq_policy *policy, const char *buf, size_t count)		\
 {									\
-	unsigned int ret;						\
+	int ret;							\
 	struct cpufreq_policy new_policy;				\
 									\
 	ret = cpufreq_get_policy(&new_policy, policy->cpu);		\
@@ -490,7 +490,7 @@ static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf)
 static ssize_t store_scaling_governor(struct cpufreq_policy *policy,
 					const char *buf, size_t count)
 {
-	unsigned int ret;
+	int ret;
 	char	str_governor[16];
 	struct cpufreq_policy new_policy;