xed-editor: Fix typelib path

We patch gobject-introspection and meson to store absolute paths to libraries in
typelibs but that requires the install_dir is an absolute path.

ref: https://github.com/NixOS/nixpkgs/commit/1b2a061c87fd079f57a05c5390a42dcc777498f0

pkgs/applications/editors/xed-editor/correct-gir-lib-path.patch

@@ -0,0 +1,13 @@
+diff --git a/xed/meson.build b/xed/meson.build
+index 7525bad..ae0814e 100644
+--- a/xed/meson.build
++++ b/xed/meson.build
+@@ -143,7 +143,7 @@ libxed = library(
+     dependencies: xed_deps,
+     include_directories: include_dirs,
+     install: true,
+-    install_dir: join_paths(libdir, 'xed')
++    install_dir: join_paths(prefix, libdir, 'xed')
+ )
+ 
+ install_headers(

pkgs/applications/editors/xed-editor/default.nix

@@ -28,6 +28,12 @@ stdenv.mkDerivation rec {
     sha256 = "sha256-MXRxzmRo/dRhp5Llib9ng1gzWW8uvzqTMjUVK8a3eJ8=";
   };
 
+  patches = [
+    # We patch gobject-introspection and meson to store absolute paths to libraries in typelibs
+    # but that requires the install_dir is an absolute path.
+    ./correct-gir-lib-path.patch
+  ];
+
   nativeBuildInputs = [
     meson
     pkg-config