Fix user/group creation - the config file must be a package source

sddm user/group creation was broken since the build that dropped
the sysusers config file as a package source. We were still
trying to generate the %pre scriptlet from SOURCE18 even though
that didn't exist any more.

Unfortunately, there still appears to be no way to actually use
an upstream packaged config file as the target of the
%sysusers_create_compat macro. I posted to devel@ about this
back in 2021, which triggered an interesting thread, but no
immediate practical solution:
https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/TFDMAU7KLMSQTKPJELHSM6PFVXIZ56GK/
so the only workaround I know of is, unfortunately, to duplicate
the config file as a package source :(

So this commit takes the generated file from a broken 0.20.0
build and adds it back as a package source. With this change,
the %pre script is once again correct and the package provides
`user(sddm)` and `group(sddm)` as it should.

sddm-systemd-sysusers.conf

@@ -0,0 +1,2 @@
+#Type Name ID GECOS                  Home directory Shell
+u     sddm -  "SDDM Greeter Account" /var/lib/sddm   -

sddm.spec

@@ -20,7 +20,7 @@
 
 Name:           sddm
 Version:        0.20.0%{?commitdate:^git%{commitdate}.%{shortcommit}}
-Release:        1%{?dist}
+Release:        2%{?dist}
 License:        GPLv2+
 Summary:        QML based desktop and login manager
 
@@ -64,6 +64,12 @@ Source14: README.scripts
 Source15: sddm.sysconfig
 # sddm x11 override config
 Source16:  sddm-x11.conf
+# sysusers config file. note these are shipped in the upstream tarball
+# but we cannot use the files from the tarball for %pre scriptlet
+# generation, so we duplicate them as source files for that purpose;
+# this is an ugly hack that should be removed if it becomes possible.
+# see https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/TFDMAU7KLMSQTKPJELHSM6PFVXIZ56GK/
+Source17:        sddm-systemd-sysusers.conf
 
 
 Provides: service(graphical-login) = sddm
@@ -196,7 +202,7 @@ cp -a %{buildroot}%{_datadir}/sddm/scripts/* \
 rm -fv %{buildroot}%{_sysconfdir}/sddm/Xsession
 
 %pre
-%sysusers_create_compat %{SOURCE18}
+%sysusers_create_compat %{SOURCE17}
 
 %post
 %systemd_post sddm.service
@@ -291,6 +297,9 @@ fi
 
 
 %changelog
+* Tue Jul 18 2023 Adam Williamson <awilliam@redhat.com> - 0.20.0-2
+- Fix user/group creation - the config file *has* to be a package source
+
 * Fri Jun 23 2023 Neal Gompa <ngompa@fedoraproject.org> - 0.20.0-1
 - Update to 0.20.0 final