ACPIPHP: prevent duplicate slot numbers when no _SUN

Dock bridges generally do not implement _SUN, yet show up as ejectable
slots.  If you have more than one ejectable slot that does not implement
SUN, with the current code you will get duplicate slot numbers.  So, if
there is no _SUN, use the current count of the number of slots found
instead.
Signed-off-by: NKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

drivers/pci/hotplug/acpiphp_glue.c

@@ -219,8 +219,13 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
 		newfunc->flags |= FUNC_HAS_DCK;
 
 	status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
-	if (ACPI_FAILURE(status))
-		sun = -1;
+	if (ACPI_FAILURE(status)) {
+		/*
+		 * use the count of the number of slots we've found
+		 * for the number of the slot
+		 */
+		sun = bridge->nr_slots+1;
+	}
 
 	/* search for objects that share the same slot */
 	for (slot = bridge->slots; slot; slot = slot->next)