ACPI: Remove acpi_start_single_object() and acpi_bus_start()

The ACPI PCI root bridge driver was the only ACPI driver implementing
the .start() callback, which isn't used by any ACPI drivers any more
now.

For this reason, acpi_start_single_object() has no purpose any more,
so remove it and all references to it.  Also remove
acpi_bus_start_device(), whose only purpose was to call
acpi_start_single_object().

Moreover, since after the removal of acpi_bus_start_device() the
only purpose of acpi_bus_start() remains to call
acpi_update_all_gpes(), move that into acpi_bus_add() and drop
acpi_bus_start() too, remove its header from acpi_bus.h and
update all of its former users accordingly.

This change was previously proposed in a different from by
Yinghai Lu.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
diff --git a/drivers/acpi/container.c b/drivers/acpi/container.c
index 811910b..98b85e3 100644
--- a/drivers/acpi/container.c
+++ b/drivers/acpi/container.c
@@ -139,24 +139,14 @@
 {
 	acpi_handle phandle;
 	struct acpi_device *pdev;
-	int result;
 
-
-	if (acpi_get_parent(handle, &phandle)) {
+	if (acpi_get_parent(handle, &phandle))
 		return -ENODEV;
-	}
 
-	if (acpi_bus_get_device(phandle, &pdev)) {
+	if (acpi_bus_get_device(phandle, &pdev))
 		return -ENODEV;
-	}
 
-	if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_DEVICE)) {
-		return -ENODEV;
-	}
-
-	result = acpi_bus_start(*device);
-
-	return result;
+	return acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_DEVICE);
 }
 
 static void container_notify_cb(acpi_handle handle, u32 type, void *context)