driver core: bus: bus_add/remove_driver() cleanups

Convert the bus_add_driver() and bus_remove_driver() functions to use
bus_to_subsys() and not use the back-pointer to the private structure.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230208111330.439504-12-gregkh@linuxfoundation.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>