Disable pgreedy in the schedulers.sh.

This test often hangs, and anyway the scheduler is still experimental.

examples/scheduler/schedulers.sh

@@ -29,6 +29,11 @@ SCHEDULERS=`STARPU_SCHED="help" ./basic_examples/hello_world 2>&1 | awk '/->/ {p
 
 for sched in $SCHEDULERS
 do
+    # XXX pgreedy often hangs, we have to fix it.
+    # Let's just disable it for now.
+    if [ "$sched" == "pgreedy" ] ; then
+        continue
+    fi
     echo "cholesky.$sched"
     STARPU_SCHED=$sched ./cholesky/cholesky_tag
     check_success $?