[virt-tools-list] libosinfo: autoconfiscate, distcheck, make tests pass (again?), etc.

[Jim Meyering]

I'm about to send a patch series that autoconfiscates libosinfo,
fixes a few bugs to make its tests pass,
makes the standard "make distcheck" test pass,
and starts to address gcc warnings.

Here are their summary lines:

      autoconfiscate
      libraries must not call chdir;  avoid getcwd, too
      avoid gcc warnings
      remove decls of unused variables
      fix failing tests  <<======= requires review
      tests: fix test-filter failure
      avoid FP unused "osname" warning
      remove more declarations of unused variables
      include <string.h> for decl of strcmp, in test programs
      fix used-uninitialized bugs
      avoid legitimate gcc used-before-set warning

I've refrained from modifying ChangeLog,
because the ChangeLog entries can serve that purpose
and don't get in the way of rebasing, reordering patches, etc.
If you'd like, I can arrange so that a ChangeLog file is generated
from the git logs and included in the release tarball created
by "make dist".

The "fix failing tests" change marked above needs review.
I did a very quick job of adjusting the code to perform
as it appears the test driver expected.  Perhaps the test
drivers expectations were wrong in this case.

Jim