[CPUFREQ] sc520_freq.c: ioremap balanced with iounmap

ioremap must be balanced by an iounmap and failing to do so can result
in a memory leak.

Tested (compilation only):
- using allmodconfig
- making sure the files are compiling without any warning/error due to
new changes
Signed-off-by: Amol Lad <amol@verismonetworks.com>
Signed-off-by: Dave Jones <davej@redhat.com>

arch/i386/kernel/cpu/cpufreq/sc520_freq.c

@@ -153,6 +153,7 @@ static struct cpufreq_driver sc520_freq_driver = {
 static int __init sc520_freq_init(void)
 {
 	struct cpuinfo_x86 *c = cpu_data;
+	int err;
 
 	/* Test if we have the right hardware */
 	if(c->x86_vendor != X86_VENDOR_AMD ||
@@ -166,7 +167,11 @@ static int __init sc520_freq_init(void)
 		return -ENOMEM;
 	}
 
-	return cpufreq_register_driver(&sc520_freq_driver);
+	err = cpufreq_register_driver(&sc520_freq_driver);
+	if (err)
+		iounmap(cpuctl);
+
+	return err;
 }