The test runs the upstream testsuite but with the installed libraries.
This is done patching the test harness to pick libffi from system's
libdir instead the ones from the build directory.
Changes in upstream commit 40a7682 break the way we patch the testsuite
and this change fixes our script to work as it did before.
Additionally, several checks on expected library directories were
improved.
This commit also fixes several shellcheck warnings.
Add main.fmf to meet new tmt testing workflow requirements.
Update runtest.sh to curent version to fix the CI failures.
Adapt runtest.sh to the new behavior under Fedora due to rpmbuild started
using specpartsdir and extra <nvr>-build directory in build path.
