hg: jigsaw/jake: Drop OS version from ModuleTarget

[alan . bateman]

Changeset: 4784877b1442
Author:    alanb
Date:      2017-02-19 19:46 +0000
URL:       http://hg.openjdk.java.net/jigsaw/jake/rev/4784877b1442

Drop OS version from ModuleTarget

! make/CreateJmods.gmk