hg: build-infra/jdk9: Fix flags for macosx.

[magnus.ihse.bursie at oracle.com]

Changeset: 2ddd4a291858
Author:    ihse
Date:      2015-11-11 19:10 +0100
URL:       http://hg.openjdk.java.net/build-infra/jdk9/rev/2ddd4a291858

Fix flags for macosx.

! common/autoconf/flags.m4
! common/autoconf/platform.m4