AIX: Link TRANSFORM modules with their dependencies.

AIX: Link TRANSFORM modules with their dependencies.

The result closely resembles linking of these modules for the "win32"
port.  Augment the $(exports_file) header so the file is also usable as
an import file.  Unfortunately, relocating an AIX installation will now
require adding $(pkglibdir) to LD_LIBRARY_PATH.  Back-patch to 9.5,
where the modules were introduced.