RFR: 8233065: PSParallelCompact::move_and_update is unused and should be removed

[Stefan Johansson]

Hi,

Please review this small fix that removes an unused function.

JBS: https://bugs.openjdk.java.net/browse/JDK-8233065
Webrev: http://cr.openjdk.java.net/~sjohanss/8233065/00/

Summary:
The function move_and_update was not removed when its last use was removed during the removal of PermGen. 

Testing:
Build and tested through mach5 (tier1)

Thanks,
Stefan