don't fail on missing doxygen Debian does not install doxygen on arch-dependent only builds. Not having doxygen installed is a fatal error (unless the --without-doxygen option is specified, which we don't want to do since we do want to build the docs in the full builds) . Alternatively we could have used something like override_dh_auto_configure-{arch,indep}. Check how libbluray is doing that..
fix cross compilation Trying to determine whether CLOCK_MONOTONIC works is in vein, because it may differ from the buildd (in theory) being a runtime property of the kernel. For compiling gavl, it is sufficient to know that the macro is defined and to assume that on Debian systems CLOCK_MONOTONIC always works when it is defined.
