cpufreq: use kzalloc() to allocate memory for cpufreq_frequency_table

Few drivers are using kmalloc() to allocate memory for frequency
tables and since we will have an additional field '.flags' in
'struct cpufreq_frequency_table', these might become unstable.
Better get these fixed by replacing kmalloc() by kzalloc() instead.

Along with that we also remove use of .driver_data from SPEAr driver
as it doesn't use it at all. Also, writing zero to .driver_data is not
required for powernow-k8 as it is already zero.

Reported-and-reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c
index 4cfdcff..3867839 100644
--- a/drivers/cpufreq/spear-cpufreq.c
+++ b/drivers/cpufreq/spear-cpufreq.c
@@ -195,18 +195,15 @@
 	cnt = prop->length / sizeof(u32);
 	val = prop->value;
 
-	freq_tbl = kmalloc(sizeof(*freq_tbl) * (cnt + 1), GFP_KERNEL);
+	freq_tbl = kzalloc(sizeof(*freq_tbl) * (cnt + 1), GFP_KERNEL);
 	if (!freq_tbl) {
 		ret = -ENOMEM;
 		goto out_put_node;
 	}
 
-	for (i = 0; i < cnt; i++) {
-		freq_tbl[i].driver_data = i;
+	for (i = 0; i < cnt; i++)
 		freq_tbl[i].frequency = be32_to_cpup(val++);
-	}
 
-	freq_tbl[i].driver_data = i;
 	freq_tbl[i].frequency = CPUFREQ_TABLE_END;
 
 	spear_cpufreq.freq_tbl = freq_tbl;