microblaze: Add topology init

Init topology subsystem by cpu registration.

Microblaze Linux kernel is fauling by
"Oops: kernel access of bad area, sig: 11"
because cpu is not initialized.
Signed-off-by: Michal Simek <monstr@monstr.eu>

arch/microblaze/kernel/setup.c

@@ -26,6 +26,7 @@
 #include <linux/cache.h>
 #include <linux/of_platform.h>
 #include <linux/dma-mapping.h>
+#include <linux/cpu.h>
 #include <asm/cacheflush.h>
 #include <asm/entry.h>
 #include <asm/cpuinfo.h>
@@ -226,5 +227,23 @@ static int __init setup_bus_notifier(void)
 
 	return 0;
 }
-
 arch_initcall(setup_bus_notifier);
+
+static DEFINE_PER_CPU(struct cpu, cpu_devices);
+
+static int __init topology_init(void)
+{
+	int i, ret;
+
+	for_each_present_cpu(i) {
+		struct cpu *c = &per_cpu(cpu_devices, i);
+
+		ret = register_cpu(c, i);
+		if (ret)
+			printk(KERN_WARNING "topology_init: register_cpu %d "
+						"failed (%d)\n", i, ret);
+	}
+
+	return 0;
+}
+subsys_initcall(topology_init);