directories to SUBDIR.${MK_TESTS} idiom
This is being done to pave the way for future work (and homogenity) in
^/projects/make-check-sandbox .
No functional change intended.
MFC after: 1 weeks
While big, the change was meant to have no effect on behavior and instead
so far we have found two regressions: one in the etcupdate tests and
another one in the games/openttd port[1].
Revert to a known working state. We will likely have to split the patch in
functional parts before bringing back the changes.
PR: 195929
Reported by: danfe, madpilot [1]
I'm starting with the easy cases. The leftovers need to be looked at a
bit more closely.
Note that this change _does_ modify the code of the old tests. This is
required in order to allow the code to locate the data files in the
source directory instead of the current directory, because Kyua
automatically changes the latter to a temporary directory.
Also note that at least one test is known to be broken here. Actually,
the test is not really broken: it's marked as a TODO but unfortunately
Kyua's TAP parser currently does not understand that. Will have to be
fixed separately.
