Migrate testserv plugin to a couple of lines of ASCII .conf files

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

tmpfiles.d/Makefile.am

@@ -5,3 +5,7 @@ tmpfilesdir           = $(tmpfiles_path)
 dist_tmpfiles_DATA    = etc.conf legacy.conf var.conf x11.conf
 dist_tmpfiles_DATA   += dnsmasq.conf frr.conf lldpd.conf openswan.conf \
 			quagga.conf sshd.conf uuidd.conf
+
+if BUILD_TESTSERV_PLUGIN
+dist_tmpfiles_DATA   += testserv.conf
+endif

tmpfiles.d/testserv.conf

@@ -0,0 +1,6 @@
+# Test service, only used for `make check`, not for public use
+
+d  /var/run/serv	0755 - - -
+d  /var/lib/serv	0755 - - -
+d  /tmp/serv		0755 - - -
+r  /run/serv.pid