hotplug: Support kernel/hotplug sysctl variable when !CONFIG_NET

The kernel/hotplug sysctl variable (/proc/sys/kernel/hotplug file) was
made conditional on CONFIG_NET by commit
f743ca5e (applied in 2.6.18) to fix
problems with undefined references in 2.6.16 when CONFIG_HOTPLUG=y &&
!CONFIG_NET, but this restriction is no longer needed.

This patch makes the kernel/hotplug sysctl variable depend only on
CONFIG_HOTPLUG.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Acked-by: Randy Dunlap <randy.dunlap@oracle.COM>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/sysctl.c

@@ -562,7 +562,7 @@ static struct ctl_table kern_table[] = {
 		.extra2		= &one,
 	},
 #endif
-#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
+#ifdef CONFIG_HOTPLUG
 	{
 		.procname	= "hotplug",
 		.data		= &uevent_helper,