hg: jdk/sandbox: For consistency, restore old name of CDS_IS_ENABLED.

[magnus.ihse.bursie at oracle.com]

Changeset: 44b59f7db03f
Author:    ihse
Date:      2020-02-19 12:17 +0100
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/44b59f7db03f

For consistency, restore old name of CDS_IS_ENABLED.

! make/autoconf/jdk-options.m4
! make/autoconf/jvm-features.m4