Usage of killall is replaced with init script. This is cleaner solution
as it does not consider some implementation detail but rather passes
that on to init script implementation.
IPKG_INSTROOT was added to prevent execution when not running in current
root. It is invalid to request reload if install-root is not current
root. In this case it can be considered harmless but it is invalid
nonetheless.
Last change is removal of `exit 0`. This caused skip of default
postinst. Execution of default postinst does no harm and is more
standard considering possible future expansion of it.
Signed-off-by: Karel Kočí <karel.koci@nic.cz>