Fix NULL ptr dereference causing kernel panic
Fix NULL ptr dereference causing kernel panic

When `service_stop_done()` is called with a `NULL` argument and no
dynamic services have been stopped, this regression is triggered.

Signed-off-by: Joachim Nilsson <583c295fd7602c168ad814279bbc3894ba65f5d6@gmail.com>

troglobit/finit,westermo/finit,westermo/finit,troglobit/finit