cpufreq: cached_resolved_idx can not be negative

It is not possible for cached_resolved_idx to be invalid here as the
cpufreq core always sets index to a positive value.

Change its type to unsigned int and fix qcom usage a bit.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/cpufreq.c

@@ -538,7 +538,7 @@ unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy,
 	policy->cached_target_freq = target_freq;
 
 	if (cpufreq_driver->target_index) {
-		int idx;
+		unsigned int idx;
 
 		idx = cpufreq_frequency_table_target(policy, target_freq,
 						     CPUFREQ_RELATION_L);

drivers/cpufreq/qcom-cpufreq-hw.c

@@ -112,13 +112,10 @@ static unsigned int qcom_cpufreq_hw_fast_switch(struct cpufreq_policy *policy,
 						unsigned int target_freq)
 {
 	void __iomem *perf_state_reg = policy->driver_data;
-	int index;
+	unsigned int index;
 	unsigned long freq;
 
 	index = policy->cached_resolved_idx;
-	if (index < 0)
-		return 0;
-
 	writel_relaxed(index, perf_state_reg);
 
 	freq = policy->freq_table[index].frequency;

include/linux/cpufreq.h

@@ -127,7 +127,7 @@ struct cpufreq_policy {
 
 	 /* Cached frequency lookup from cpufreq_driver_resolve_freq. */
 	unsigned int cached_target_freq;
-	int cached_resolved_idx;
+	unsigned int cached_resolved_idx;
 
 	/* Synchronization for frequency transitions */
 	bool			transition_ongoing; /* Tracks transition status */