hg: jdk6/jdk6/corba: 6790292: BOOTDIR of jdk6 u12 will not work with jdk7 builds

[kelly . ohair]

Changeset: a987ccd6f37b
Author:    ohair
Date:      2012-01-04 11:33 -0800
URL:       http://hg.openjdk.java.net/jdk6/jdk6/corba/rev/a987ccd6f37b

6790292: BOOTDIR of jdk6 u12 will not work with jdk7 builds
Reviewed-by: tbell

! make/common/Rules.gmk