AIDACC: tests/Makefile.sub: fix aidacc-tests-clean and aidacc-tests-check being ignored
AIDACC: tests/Makefile.sub: fix aidacc-tests-clean and aidacc-tests-check being ignored

Rules in Makefile.sub files must follow this naming convention:
  sub-dir-name-rulename
That way clashes are avoided and make invokations in sub directoires can be properly
forwarded via a local GNUmakefile and misc/subdirs.mk.

Signed-off-by: Tim Janik <6ec6ff229c4e1c5bbd5933ee92e6c5832ff023bb@gnu.org>

swesterfeld/beast,swesterfeld/beast,tim-janik/beast,tim-janik/beast,swesterfeld/beast,tim-janik/beast,tim-janik/beast,swesterfeld/beast,tim-janik/beast,swesterfeld/beast,swesterfeld/beast,tim-janik/beast,swesterfeld/beast,tim-janik/beast