pkgs/data/fonts: merge back the split otb output

Since the Pango issue 457[1] has been fixed and Nixpkgs patched, it's no
longer necessary to keep X11 and .otb fonts in separate outputs (previously
they would cause application to display broken fonts).

[1]: https://gitlab.gnome.org/GNOME/pango/-/issues/457

pkgs/data/fonts/terminus-font/default.nix

@@ -35,14 +35,12 @@ stdenv.mkDerivation rec {
 
   postInstall = ''
     # install otb fonts (for GTK applications)
-    install -m 644 -D *.otb -t "$otb/share/fonts/misc";
-    mkfontdir "$otb/share/fonts/misc"
+    install -m 644 -D *.otb -t "$out/share/fonts/misc";
+    mkfontdir "$out/share/fonts/misc"
   '';
 
   installTargets = [ "install" "fontdir" ];
 
-  outputs = [ "out" "otb" ];
-
   meta = with stdenv.lib; {
     description = "A clean fixed width font";
     longDescription = ''