meson: Disallow DbgHelp for UWP build

Most symbols in DbgHelp.h are not allowed for UWP

Part-of: <gstreamer/gstreamer!670>
34 jobs for backport-mr-665-into-1.18-dbghelp-uwp-disable in 27 minutes and 37 seconds (queued for 1 minute and 17 seconds)