RFR 8068233: java/lang/management/ThreadMXBean/ThreadMXBeanStateTest.java is still in exclude list

[Jaroslav Bachorik]

Please, review this simple ProblemList.txt update

Issue : https://bugs.openjdk.java.net/browse/JDK-8068233
Webrev: http://cr.openjdk.java.net/~jbachorik/8068233/webrev.00

Part of the fix for JDK-8058506 was lost after incorrect merging of repo 
during modularization of JDK. This fix reintroduces the lost change.

Thanks,

-JB-