Log Message:
GCC generates and uses its own libtool to build shared libraries, and
the resulting shared library names don't necessarily match the NetBSD
names.  Instead of hardcoding the shared library names in the PLISTs,
only list the libtool archives in the PLISTs and dynamically determine
the shared library names at post-install time and insert them into
the PLIST.  This fixes PLIST errors on non-NetBSD platforms.

All of the magic is done in pkgsrc/lang/gcc3/language.mk.  This should
probably be generalized into something that could be used by all
packages that use libtool.