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>

drivers/cpufreq/ia64-acpi-cpufreq.c

@@ -254,7 +254,7 @@ acpi_cpufreq_cpu_init (
 	}
 
 	/* alloc freq_table */
-	data->freq_table = kmalloc(sizeof(*data->freq_table) *
+	data->freq_table = kzalloc(sizeof(*data->freq_table) *
 	                           (data->acpi_data.state_count + 1),
 	                           GFP_KERNEL);
 	if (!data->freq_table) {