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/envypn-font/default.nix

@@ -25,14 +25,10 @@ stdenv.mkDerivation {
   '';
 
   installPhase = ''
-    install -D -m 644 -t "$out/share/fonts/misc" *.pcf.gz
-    install -D -m 644 -t "$otb/share/fonts/misc" *.otb
+    install -D -m 644 -t "$out/share/fonts/misc" *.otb *.pcf.gz
     mkfontdir "$out/share/fonts/misc"
-    mkfontdir "$otb/share/fonts/misc"
   '';
 
-  outputs = [ "out" "otb" ];
-
   meta = with stdenv.lib; {
     description = ''
       Readable bitmap font inspired by Envy Code R