libjxl: Fix static compilation

Co-authored-by: Alyssa Ross <hi@alyssa.is>

pkgs/development/libraries/libjxl/default.nix

@@ -69,11 +69,14 @@ stdenv.mkDerivation rec {
     pkg-config
   ] ++ lib.optionals buildDocs [
     asciidoc
-    graphviz
     doxygen
     python3
   ];
 
+  depsBuildBuild = lib.optionals buildDocs [
+    graphviz
+  ];
+
   # Functionality not currently provided by this package
   # that the cmake build can apparently use:
   #     OpenGL/GLUT (for Examples -> comparison with sjpeg)
@@ -125,6 +128,8 @@ stdenv.mkDerivation rec {
     # * the `gdk-pixbuf` one, which allows applications like `eog` to load jpeg-xl files
     # * the `gimp` one, which allows GIMP to load jpeg-xl files
     # "-DJPEGXL_ENABLE_PLUGINS=ON"
+  ] ++ lib.optionals stdenv.hostPlatform.isStatic [
+   "-DJPEGXL_STATIC=ON"
   ];
 
   LDFLAGS = lib.optionalString stdenv.hostPlatform.isRiscV "-latomic";