tests: Fix 'make test' for i686 hosts (build regression)

tests: Fix 'make test' for i686 hosts (build regression)

'make test' is broken at least since commit
baacf04799ace72a9c735dd9306a1ceaf305e7cf. Several source files were moved
to util/, and some of them there split, so add the missing prefix and new
files to fix the compiler and linker errors.

There remain more issues, but these changes allow running the test on a
Linux i686 host.

Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>