Finally eradicate CONFIG_HOTPLUG

Ever since commit 45f035ab9b8f ("CONFIG_HOTPLUG should be always on"),
it has been basically impossible to build a kernel with CONFIG_HOTPLUG
turned off.  Remove all the remaining references to it.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/usb/hotplug.txt b/Documentation/usb/hotplug.txt
index 4c94571..6424b13 100644
--- a/Documentation/usb/hotplug.txt
+++ b/Documentation/usb/hotplug.txt
@@ -33,9 +33,9 @@
 
 KERNEL HOTPLUG HELPER (/sbin/hotplug)
 
-When you compile with CONFIG_HOTPLUG, you get a new kernel parameter:
-/proc/sys/kernel/hotplug, which normally holds the pathname "/sbin/hotplug".
-That parameter names a program which the kernel may invoke at various times.
+There is a kernel parameter: /proc/sys/kernel/hotplug, which normally
+holds the pathname "/sbin/hotplug".  That parameter names a program
+which the kernel may invoke at various times.
 
 The /sbin/hotplug program can be invoked by any subsystem as part of its
 reaction to a configuration change, from a thread in that subsystem.