check_software: fix false positive with software updated in place
The check for shared part referencing software was not reporting a false positive in this scenario:
- install a software with shared parts referencing non shared part from software
- update software "in place", no longer using this broken shared part
because check software was checking all installed shared parts, regardless of whether they were used by the software being checked or not, the shared part from 1 was still reported as referencing software, which is incorrect as it is no longer used.
The fix consists in only checking shared parts that are referenced in .installed.cfg for the software being checked.