gnu: gdk-pixbuf: Merge the two 'arguments' fields.

This is a followup to commit 0d5ddad.

* gnu/packages/gtk.scm (gdk-pixbuf): Merge the two 'arguments' fields.

gnu/packages/gtk.scm

@@ -335,20 +335,9 @@ printing and other features typical of a source code editor.")
               "062x2gqd7p6yxhxlib1ha4l3gk9ihcj080hrwwv9vmlmybb064hi"))))
    (build-system gnu-build-system)
    (arguments
-    '(#:configure-flags '("--with-x11")))
+    '(#:configure-flags '("--with-x11")
-   (propagated-inputs ; required by gdk-pixbuf-2.0.pc
+      #:phases
-    `(("glib" ,glib)
+      (modify-phases %standard-phases
-      ("libpng" ,libpng)))
-   (inputs
-    `(("libjpeg" ,libjpeg)
-      ("libtiff" ,libtiff)
-      ("libx11"  ,libx11)))
-   (native-inputs
-     `(("pkg-config" ,pkg-config)
-       ("glib" ,glib "bin")                               ; glib-mkenums, etc.
-       ("gobject-introspection", gobject-introspection))) ; g-ir-compiler, etc.
-   (arguments
-    `(#:phases (modify-phases %standard-phases
         (add-after
          'unpack 'disable-failing-tests
          (lambda _
@@ -363,6 +352,17 @@ printing and other features typical of a source code editor.")
              ;; (gdk-pixbuf-error-quark, 0)
              (("pixbuf-jpeg\\$\\(EXEEXT\\) ") ""))
            #t)))))
+   (propagated-inputs ; required by gdk-pixbuf-2.0.pc
+    `(("glib" ,glib)
+      ("libpng" ,libpng)))
+   (inputs
+    `(("libjpeg" ,libjpeg)
+      ("libtiff" ,libtiff)
+      ("libx11"  ,libx11)))
+   (native-inputs
+     `(("pkg-config" ,pkg-config)
+       ("glib" ,glib "bin")                               ; glib-mkenums, etc.
+       ("gobject-introspection", gobject-introspection))) ; g-ir-compiler, etc.
    (synopsis "GNOME image loading and manipulation library")
    (description
     "GdkPixbuf is a library for image loading and manipulation developed