hg: jdk9/sandbox: Clear up passing of make variables.

[magnus.ihse.bursie at oracle.com]

Changeset: 32ff489a4f74
Author:    ihse
Date:      2015-03-23 16:28 +0100
URL:       http://hg.openjdk.java.net/jdk9/sandbox/rev/32ff489a4f74

Clear up passing of make variables.

! common/autoconf/spec.gmk.in
! make/Init.gmk
! make/InitSupport.gmk
! make/MakeHelpers.gmk