Drop the SystemdService line in dbus service files

I don't think we can dbus activate systemd services on

the session bus (we don't have a user bus, and I'm

pretty sure we don't have systemd --user)

This commit just drops the lines, so dbus can activate on

its own.

diff -up flatpak-0.8.8/session-helper/org.freedesktop.Flatpak.service.in.no-user-systemd flatpak-0.8.8/session-helper/org.freedesktop.Flatpak.service.in

--- flatpak-0.8.8/session-helper/org.freedesktop.Flatpak.service.in.no-user-systemd	2017-11-08 16:33:21.045226761 -0500

+++ flatpak-0.8.8/session-helper/org.freedesktop.Flatpak.service.in	2017-11-08 16:33:38.361037649 -0500

@@ -1,4 +1,3 @@

 [D-BUS Service]

 Name=org.freedesktop.Flatpak

 Exec=@libexecdir@/flatpak-session-helper

-SystemdService=flatpak-session-helper.service

--- flatpak-1.0.1/portal/org.freedesktop.portal.Flatpak.service.in.no-user-systemd	2018-05-30 14:58:57.000000000 +0200

+++ flatpak-1.0.1/portal/org.freedesktop.portal.Flatpak.service.in	2018-09-12 12:11:27.428215430 +0200

@@ -1,4 +1,3 @@

 [D-BUS Service]

 Name=org.freedesktop.portal.Flatpak

 Exec=@libexecdir@/flatpak-portal

-SystemdService=flatpak-portal.service