base-files: use restart if no reload hook for service

This was also working before, with a slightly
different semantic.

[ Original semantic ]
If no reload hooks was implemented, the default one would
kick in, it would return fail, and restart would happen.

This would happen also in the case where a reload hook
would be implemented, it would fail, and it would restart
the service.

[ New semantic ]
The default reload hook calls restart.
Services can implement their own reload.

If reload fails, then the '/etc/init.d/<service> reload'
would return a non-zero code, and the caller can choose
a way to handle this.

Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>