RFR (S): 8029957: PPC64 (part 213): cppInterpreter: memory ordering for object initialization

[Lindenmaier, Goetz]

Hi,

this change adds StoreStore barriers after object initialization and
after constructor calls in the C++ interpreter.  This assures no uninitialized
objects or final fields are visible.
http://cr.openjdk.java.net/~goetz/webrevs/8029957-0-moci/

Please review and test this change.

Best regards,
  Goetz.