hg: jdk9/sandbox: * Properly filter out any -j setting before calling main target.

[magnus.ihse.bursie at oracle.com]

Changeset: 22f328299852
Author:    ihse
Date:      2015-03-25 11:56 +0100
URL:       http://hg.openjdk.java.net/jdk9/sandbox/rev/22f328299852

* Properly filter out any -j setting before calling main target.
* Revert to testing for --jobserver

! make/Help.gmk
! make/Init.gmk
! make/InitSupport.gmk