installer: Fix path to libgetuid.so again. Hardcode it.

Hopefully fixes fdo#67388. I can't reproduce here.

Change-Id: I5bcbb59a0f49e925d60f225b0f8f925d6d5dc468
Add back check for missing libgetuid.so.

If the library does not work, things like fdo#67388 happen.

Change-Id: I3390fdb6f2cdf24145ddde4466146f91e5dfde82