Finally eradicate CONFIG_HOTPLUG

Ever since commit 45f035ab9b ("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>

arch/powerpc/mm/tlb_hash64.c

@@ -183,8 +183,8 @@ void tlb_flush(struct mmu_gather *tlb)
  * since 64K pages may overlap with other bridges when using 64K pages
  * with 4K HW pages on IO space.
  *
- * Because of that usage pattern, it's only available with CONFIG_HOTPLUG
- * and is implemented for small size rather than speed.
+ * Because of that usage pattern, it is implemented for small size rather
+ * than speed.
  */
 void __flush_hash_table_range(struct mm_struct *mm, unsigned long start,
 			      unsigned long end)