Request for review: 8010518 Move deprecating CMSIncrementalMode from Arguments::check_deprecated_gcs() to Arguments::check_deprecated_gc_flags()

[Tao Mao]

A simple changeset. Need a reviewer!

8010518 Move deprecating CMSIncrementalMode from 
Arguments::check_deprecated_gcs() to Arguments::check_deprecated_gc_flags()
https://jbs.oracle.com/bugs/browse/JDK-8010518

webrev:
http://cr.openjdk.java.net/~tamao/8010518/webrev.00/

changeset:
Cleanup suggested by Bengt.