RFR: JDK-8140762 Specifying --without-LIB if not needed should not result in warning

[Magnus Ihse Bursie]

If we specify e.g. --without-cups on a platform where cups is neither 
needed nor used, we will get a warning that --with-cups is ignored. In 
fact, specifying --without-X when X is not needed is the default and it 
should just be silently skipped by.

Bug: https://bugs.openjdk.java.net/browse/JDK-8140762
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8140762-no-warning-for-without-lib/webrev.01


/Magnus