Clean up after java/openjdk6 and java/openjdk6-jre removal

java/openjdk6 support was removed from Mk/bsd.java.mk (r512662) and
java/openjdk6 and java/openjdk6-jre were removed from the ports tree
(r512663).  Now this patch completely removes remaining stuff from the
ports tree.

PR:			241953 (exp-run)
Reviewed by:		glewis
Approved by:		portmgr (antoine)
Differential Revision:	https://reviews.freebsd.org/D22342

java/eclipse-drjava/Makefile

@@ -19,7 +19,6 @@ NO_BUILD=	yes
 NO_WRKSUBDIR=	yes
 USE_JAVA=	yes
 
-JAVA_VERSION=	1.6+
 JAVA_OS=	native
 
 DATADIR=	${PREFIX}/lib/eclipse/plugins