cpufreq: ppc: Fix integer overflow in expression

On 32-bit, "12 * NSEC_PER_SEC" doesn't fit in "unsigned long"
(NSEC_PER_SEC is a "long" constant), causing an integer overflow:

drivers/cpufreq/ppc-corenet-cpufreq.c: In function 'corenet_cpufreq_cpu_init':
drivers/cpufreq/ppc-corenet-cpufreq.c:211:9: warning: integer overflow in expression [-Woverflow]

Force the intermediate to be 64-bit by adding an "ULL" suffix to the
constant multiplier to fix this.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/ppc-corenet-cpufreq.c

@@ -206,7 +206,7 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
 		per_cpu(cpu_data, i) = data;
 
 	policy->cpuinfo.transition_latency =
-				(12 * NSEC_PER_SEC) / fsl_get_sys_freq();
+				(12ULL * NSEC_PER_SEC) / fsl_get_sys_freq();
 	of_node_put(np);
 
 	return 0;