package/xscreensaver: add gdk-pixbuf-xlib dependency

gdk-pixbuf-xlib dependency is needed since bump of gdk-pixbuf to version
2.42.2 in commit a7b51ed3013c919b293deb95299e33363fb9df70 to avoid the
following "hidden" warnings:

   Warning: GTK version 2.24.33 was found, but at least one supporting
            library (gdk-pixbuf-xlib-2.0) was not, so GTK can't be used.
            Perhaps some of the development packages are not installed?

   Warning: The GTK libraries do not seem to be available; the
            `xscreensaver-demo' program requires them.

   Warning: The GDK-Pixbuf library was not found.

            The PNG library is being used instead.

            Some of the demos will not use images as much as they could.
            You should consider installing GDK-Pixbuf and re-running
            configure.

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 35f02050be12b86cdd2220e09c72fd2586346068)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/xscreensaver/Config.in

@@ -8,6 +8,7 @@ config BR2_PACKAGE_XSCREENSAVER
 	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # libgtk2 -> pango -> harfbuzz
 	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8 # libgtk2 -> pango -> harfbuzz
 	select BR2_PACKAGE_GDK_PIXBUF
+	select BR2_PACKAGE_GDK_PIXBUF_XLIB
 	select BR2_PACKAGE_LIBGLU if BR2_PACKAGE_HAS_LIBGL
 	select BR2_PACKAGE_LIBGTK2
 	select BR2_PACKAGE_LIBXML2

package/xscreensaver/xscreensaver.mk

@@ -15,6 +15,7 @@ XSCREENSAVER_SELINUX_MODULES = xdg xscreensaver xserver
 
 XSCREENSAVER_DEPENDENCIES = \
 	gdk-pixbuf \
+	gdk-pixbuf-xlib \
 	jpeg \
 	libgtk2 \
 	libxml2 \