RFR: 8248545: Remove unneeded warning suppression of MSVC++ 4521/4522

[Kim Barrett]

Please review this change that removes the conditional suppression of
the MSVC++ warnings 4521 and 4522.  These warnings no longer get
triggered by the oop class.

4521: 'class' : multiple copy constructors specified
4522: 'class' : multiple assignment operators specified

These were triggered by the existence of both normal and volatile
qualified copy constructors and assignment operators for the class
oop, which is only defined as a class when CHECK_UNHANDLED_OOPS is
true.

CR:
https://bugs.openjdk.java.net/browse/JDK-8248545

Webrev:
https://cr.openjdk.java.net/~kbarrett/8248545/open.00/

Testing:
Build all Oracle supported Windows variants, including forcing
-DCHECK_UNHANDLED_OOPS in a fastdebug build.  (The build system
currently never enables CHECK_UNHANDLED_OOPS for Windows; I changed
that for testing.)