hg: build-infra/jdk8: Fix partial: JDK-8001594 Enable closed builds on Windows with Cygwin and MinGW/MSYS

[tim.bell at oracle.com]

Changeset: c0182aaefcb2
Author:    tbell
Date:      2013-01-03 01:49 -0800
URL:       http://hg.openjdk.java.net/build-infra/jdk8/rev/c0182aaefcb2

Fix partial: JDK-8001594 Enable closed builds on Windows with Cygwin and MinGW/MSYS
Support for Client.jar (Main-Class: oracle.client.ccss.Client) and SIGN_FLAG=1

! common/autoconf/generated-configure.sh
! common/makefiles/Jprt.gmk