rtld: Do not install libmap.conf when installing the COMPAT32 version

This has the effect of installing the same file twice at the same location
and confuse pkgbase as we add this file twice in the package config part.

MFC after: 1 week
Sponsored by: Beckhoff Automation GmbH & Co. KG

(cherry picked from commit d0f0e0bd741af867582ceede8ac1b0aec90eae2d)