Linking libxml2 against ICU libraries has a nasty side effect:
The URE library javavm.dll links against URE libxml2.dll, which
is now linked against OOO icuuc53.dll; when a URE program, like
uno.exe, tries to load javavm.dll it fails because the OOO layer
"program" dir is not on PATH; this breaks the installation of Java
extensions.

Fix that by splitting up ICU libraries and putting the required ones
into URE layer.

(regression from 7515b1a9)

Change-Id: If98dd0357162cb632d9762cd2d20162de5eb1a52