[CPUFREQ] fix panic in powernow_k8_verify on MP but PSB systems.

Instead of -ENODEV; powernow_k8_cpu_init returns 0 if it's running on a MP
system but PSB BIOS is tried... this causes a panic in
powernow_k8_verify, as can be seen at
http://forums.gentoo.org/viewtopic.php?t=177423Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Dominik Brodowski <linux@brodo.de>

arch/i386/kernel/cpu/cpufreq/powernow-k8.c

@@ -949,7 +949,7 @@ static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
 		if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
 			printk(KERN_INFO PFX "MP systems not supported by PSB BIOS structure\n");
 			kfree(data);
-			return 0;
+			return -ENODEV;
 		}
 		rc = find_psb_table(data);
 		if (rc) {