We're going to have a few more CI-related files in a second, and
it makes sense to have a separate directory for them rather than
littering the root directory.
$(CI_SCRATCHDIR) can now also be created inside the CI directory,
and as a bonus the make rune necessary to start CI builds without
running configure first becomes shorter.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
