hg: build-infra/jdk9/hotspot: Even more CFLAGS cleanup.

[magnus.ihse.bursie at oracle.com]

Changeset: 29ea2307fc10
Author:    ihse
Date:      2016-01-15 14:35 +0100
URL:       http://hg.openjdk.java.net/build-infra/jdk9/hotspot/rev/29ea2307fc10

Even more CFLAGS cleanup.

! makefiles/Common.gmk
! makefiles/Dtrace.gmk
! makefiles/JvmPlatforms.gmk