cpu: Do not return errors from cpu_dev_init() which will be ignored

cpu_dev_init() is only called from driver_init(), which does not check
its return value.  Therefore make cpu_dev_init() return void.

We must register the CPU subsystem, so panic if this fails.

If sched_create_sysfs_power_savings_entries() fails, the damage is
contained, so ignore this (as before).
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/base/base.h

@@ -94,7 +94,7 @@ extern int hypervisor_init(void);
 static inline int hypervisor_init(void) { return 0; }
 #endif
 extern int platform_bus_init(void);
-extern int cpu_dev_init(void);
+extern void cpu_dev_init(void);
 
 extern int bus_add_device(struct device *dev);
 extern void bus_probe_device(struct device *dev);

drivers/base/cpu.c

@@ -2,6 +2,7 @@
  * CPU subsystem support
  */
 
+#include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/sched.h>
@@ -274,16 +275,12 @@ bool cpu_is_hotpluggable(unsigned cpu)
 }
 EXPORT_SYMBOL_GPL(cpu_is_hotpluggable);
 
-int __init cpu_dev_init(void)
+void __init cpu_dev_init(void)
 {
-	int err;
-
-	err = subsys_system_register(&cpu_subsys, cpu_root_attr_groups);
-	if (err)
-		return err;
+	if (subsys_system_register(&cpu_subsys, cpu_root_attr_groups))
+		panic("Failed to register CPU subsystem");
 
 #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
-	err = sched_create_sysfs_power_savings_entries(cpu_subsys.dev_root);
+	sched_create_sysfs_power_savings_entries(cpu_subsys.dev_root);
 #endif
-	return err;
 }