RFR(T) 8223414: ProblemList java/lang/ref/ReachabilityFenceTest.java when running in Graal as JIT mode

[Ekaterina Pavlova]

Hi all,

Please review trivial change which adds java/lang/ref/ReachabilityFenceTest.java in Graal problem list.
java/lang/ref/ReachabilityFenceTest.java regularly fails when running in Graal as JIT mode.
Vladimir I. provided detailed explanations (see JDK-8146090) why this test could fail with Graal.
It seems reasonable to disable this tests from running with Graal till we have libgraal.

     JBS: https://bugs.openjdk.java.net/browse/JDK-8223414
  webrev: http://cr.openjdk.java.net/~epavlova//8223414/webrev.00/index.html

thanks,
-katya