build: No need to clean org.freedesktop.portal.Desktop.service twice
build: No need to clean org.freedesktop.portal.Desktop.service twice

Everything in ${dbus_service_DATA} is already added to CLEANFILES
by ./Makefile.am.

Signed-off-by: Simon McVittie <0e1aea601907c1a85c2dc96e5ea37e23c58d2e9b@debian.org>

matthiasclasen/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,flatpak/xdg-desktop-portal