Use macro for directory with systemd user environment generators

Thanks to ldv@ for poiting to existance of this macro

kometa-xdg.spec

@@ -8,6 +8,7 @@ Release: alt1
 Source0: kometa-xdg-%version.tar
 Source1: COPYING
 BuildArch: noarch
+BuildRequires: rpm-macros-systemd
 
 %description
 XDG desktop settings for Kometa distros
@@ -31,8 +32,7 @@ DE-независимые настройки рабочих окружений
 %doc COPYING
 %dir /etc/xdg/kometa
 %_bindir/kometa-xdg-env
-# XXX ALT has no macro for /usr/lib/systemd/...
-/usr/lib/systemd/user-environment-generators/10-kometa-xdg.sh
+%_user_env_gen_dir/10-kometa-xdg.sh
 /etc/profile.d/10-kometa-xdg.sh
 
 #--------------------------------------------------------------
@@ -76,7 +76,7 @@ install -m0755 scripts/kometa-xdg-env %buildroot%_bindir/kometa-xdg-env
 # for console
 install -m0755 scripts/profile.sh %buildroot/etc/profile.d/10-kometa-xdg.sh
 # for dbus services
-install -m0755 scripts/systemd.sh %buildroot/usr/lib/systemd/user-environment-generators/10-kometa-xdg.sh
+install -m0755 scripts/systemd.sh %buildroot%_user_env_gen_dir/10-kometa-xdg.sh
 
 mkdir -p %buildroot/etc/xdg/kometa
 install -m0644 plasma5/* %buildroot/etc/xdg/kometa