IFP: dbus service file corrected

If I understand 1a59af8 correctly,
intention was to trigger re-connection attempt to the system bus
using sss_signal -> monitor -> sssd_ifp chain for a "monitor" activated
sssd_ifp.
Later 9222a4f added support for systemd
dbus-socket activation using "SystemdService=sssd-ifp.service" option
in dbus service file. But it also replaced 'Exec=sss_signal' with
'Exec=sssd_ifp' on systemd-enabled systems. I think it doesn't make much
sense: on systemd-enabled system "SystemdService=" is used. Moreover,
it break original purpose: if this would be used then a new instance of
sssd_ifp would be spawn instead of re-connection attempt.
This patch simply removes "Exec=" from dbus service file in case package
is built with systemd support.

Makefile.am

@@ -90,6 +90,7 @@ sssdkcmdatadir = $(datadir)/sssd-kcm
 deskprofilepath = $(sss_statedir)/deskprofile
 
 if HAVE_SYSTEMD_UNIT
+ifp_dbus_exec =
 ifp_exec_cmd = $(sssdlibexecdir)/sssd_ifp --uid 0 --gid 0 --dbus-activated
 ifp_systemdservice = SystemdService=sssd-ifp.service
 ifp_restart = Restart=on-failure
@@ -105,7 +106,8 @@ if SSSD_NON_ROOT_USER
 additional_caps = CAP_DAC_OVERRIDE
 endif
 else
-ifp_exec_cmd = $(sssdlibexecdir)/sss_signal
+ifp_dbus_exec = Exec=$(sssdlibexecdir)/sss_signal
+ifp_exec_cmd =
 ifp_systemdservice =
 ifp_restart =
 endif
@@ -1746,6 +1748,7 @@ EXTRA_DIST += \
 
 ifp_edit_cmd = $(edit_cmd) \
         -e 's|@ifp_exec_cmd[@]|$(ifp_exec_cmd)|g' \
+        -e 's|@ifp_dbus_exec[@]|$(ifp_dbus_exec)|g' \
         -e 's|@ifp_systemdservice[@]|$(ifp_systemdservice)|g' \
         -e 's|@ifp_restart[@]|$(ifp_restart)|g'
 

src/responder/ifp/org.freedesktop.sssd.infopipe.service.in

@@ -1,5 +1,4 @@
 [D-BUS Service]
 Name=org.freedesktop.sssd.infopipe
-Exec=@ifp_exec_cmd@
-User=root
+@ifp_dbus_exec@
 @ifp_systemdservice@