hg: build-infra/jdk9/hotspot: I just realized this means that all platforms use tiered compilation on server. Simplify accordingly.

[magnus.ihse.bursie at oracle.com]

Changeset: d83c603fbc07
Author:    ihse
Date:      2016-01-28 08:26 +0100
URL:       http://hg.openjdk.java.net/build-infra/jdk9/hotspot/rev/d83c603fbc07

I just realized this means that all platforms use tiered compilation on server. Simplify accordingly.

! makefiles/JvmFeaturesConf.gmk