[PATCH] shpchp: Implement get_address callback

The following patch implements .get_address callback of
hotplug_slot_ops for SHPCHP driver. With this patch, we
can see bus address of hotplug slots as follows:

	$ cat address
	0000:0b:01

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>