[PATCH] acpi hotplug: clean up notify handlers on acpiphp unload

A root bridge may not have directly attached hotpluggable slots under it.
Instead, it may have p2p bridges with slots under it.  In this case, we need
to clean up the p2p bridges and slots properly too.  Patch below applies on
top of the original patch, and fixes this problem.  Without this, acpiphp
leaves behind notify handlers on module unload, and subsequent module load
attempts don't work properly too.  Patch was tested on an ia64 Tiger4 box.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>