[trivial] RFR: 8242631: Missing but used special functions for some classes

[Kim Barrett]

Please review this trivial change to a couple of classes to eliminate
gcc9 deprecation warnings for them when compiling for C++11 or later.
See the CR for more details about the warnings.

BCEscapeAnalyzer::ArgumentMap has an implicitly defined copy
constructor and a user-defined copy assignment operator.  Since the
copy assignment operator is functionally equivalent to the default,
removed it.

Various subtypes of oop had an implicitly defined copy constructor;
made it explicit.

There are a few more like these, but I may address them differently.

CR:
https://bugs.openjdk.java.net/browse/JDK-8242631

Webrev:
https://cr.openjdk.java.net/~kbarrett/8242631/open.00/

Testing:
mach5 tier1