-fsanitize=address does not like -z defs

Change-Id: Id2a5c3009b46f9f91706b433411ca9f9c3cb7e39
Reviewed-on: https://gerrit.libreoffice.org/9334
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>