complibs/cloog: remove old CLooG/PPL versions

Those versions are no longer available upstream. They have purely and
simply disapeared, without leaving any trace of their mere existences.

Just keep the latest cloog-ppl-0.15.11, which still exists on the gcc
infra mirror (but for how long?)

Reported-by: Guillaume FLORENCE-COURTAND <gflorenc@laposte.net>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 # Default test suite configuration

 # Default DejaGnu configuration

 DG_TOOLNAME = gcc

 DG_TARGET_HOSTNAME = 127.0.0.1

 DG_TARGET_USERNAME = root

 # Default tests

 DG_C_TESTS = 

 DG_CPP_TESTS =