driver core: bus: move bus notifier logic into bus.c

driver core: bus: move bus notifier logic into bus.c

The logic to touch the bus notifier was open-coded in numberous places
in the driver core.  Clean that up by creating a local bus_notify()
function and have everyone call this function instead, making the
reading of the caller code simpler and easier to maintain over time.

Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230111092331.3946745-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>