[8u60] Request Review: 8068548 jdeps needs a different mechanism to recognize javax.jnlp as supported API

[Mandy Chung]

Webrev at :
   http://cr.openjdk.java.net/~mchung/jdk8u/webrevs/8068548/webrev.00/

JBS:  https://bugs.openjdk.java.net/browse/JDK-8068548

This is 1-line fix.  The 8u40 fix for JDK-8039007 breaks TCK signature test
and @jdk.Exported should only be used by JDK-specific API.  jdeps simply 
hardcodes it.

Mandy