Don't call pkcon -p repo-list

Using pkcon in rich-core-dumper can cause a deadlock if the crashed
app is called from an rpm scriptlet. Pkcon is still needed when stack
traces on device are enabled; this will be handled separately.
Avoid using pkcon when running RPM scriptlet is detected
Merge pull request #41 from xhaakon/pkcon-deadlock

Pkcon deadlock