RFR [11u] 8232572: Add hooks for custom output dir in Bundles.gmk

[Langer, Christoph]

Hi,

please review this Oracle parity backport.

Bug: https://bugs.openjdk.java.net/browse/JDK-8232572
Original Change: https://hg.openjdk.java.net/jdk/jdk/rev/ae0af9fb3dbb
Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8232572.11u/

I had to manually bring some hunks to the right position in the file. The $$(call MakeTargetDir) does not yet exist as it was only introduced with JDK-8211724. So I just add the LogWarn call as first command in the recipe.

Thanks and best regards
Christoph