8193758: Update copyright headers of files in src tree that are missing "Classpath" exception

[Alan Bateman]

There are a small number of files in jdk/jdk10 that have the GPL header 
rather than the GPL and "Classpath" exception. This came up last week on 
jdk-dev. I need a Reviewer to adjust these files. The webrev with the 
changes is here:
    http://cr.openjdk.java.net/~alanb/8193758/webrev/

There are a few other tools used in the build that may need to be 
adjusted too. If needed, there will be a follow-up issue for those.

-Alan