src: Move DLOPEN_LIBS to libraries introducing the dependency

src: Move DLOPEN_LIBS to libraries introducing the dependency

There are few places where dlopen() is called. This call means we
have to link with DLOPEN_LIBS. However, instead of having each
final, installable library linking with it, move the directive to
the source that introduced the dependency.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>