RFR: JDK-8129969: Switch JPRT configuration to use devkits for Windows and Macosx

[Erik Joelsson]

Hello,

Please review this change for the Oracle internal JPRT configuration for 
building jdk9. This change flips the switch for JPRT to start using 
devkits for building jdk9 on Windows and Macosx, instead of preinstalled 
versions of Visual Studio and Xcode. The versions of the compilers stay 
the same for now, so nothing should really change in the product. Making 
this change will make it much easier to change compiler versions in the 
future.

Bug: https://bugs.openjdk.java.net/browse/JDK-8129969
Patch:

diff -r 2f143b1e68d5 make/jprt.properties
--- a/make/jprt.properties
+++ b/make/jprt.properties
@@ -123,11 +123,13 @@
      ${my.i586.default.build.configure.args}                \
      ${jprt.productOpen.build.configure.args}

-jprt.windows_i586_6.2.build.configure.args= \
- --with-toolchain-version=2013 \
+jprt.windows_i586.build.configure.args= \
+    --with-devkit=$VS2013_HOME \
      ${jprt.i586.build.configure.args}
-jprt.windows_x64_6.2.build.configure.args= \
-    --with-toolchain-version=2013
+jprt.windows_x64.build.configure.args= \
+    --with-devkit=$VS2013_HOME
+jprt.macosx_x64.build.configure.args= \
+    --with-devkit=$XCODE_511_HOME

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