...and at least issue a SAL_INFO when it's missing (there may theoretically be
multiple directories, and it need not be present in every one, so nothing
stronger than SAL_INFO can be used)

Change-Id: I9b7257a551626e5ad081cfb75422a8bd71b86aa4
Reviewed-on: https://gerrit.libreoffice.org/42714Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>