cairo: script backend needs png

Fixes http://autobuild.buildroot.org/results/7b21c60d7ba1a8df8910d104e21d4545cb37a4c6

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/cairo/Config.in

@@ -30,7 +30,7 @@ config BR2_PACKAGE_CAIRO_PNG
 
 config BR2_PACKAGE_CAIRO_SCRIPT
 	bool "script support"
-	select BR2_PACKAGE_ZLIB
+	select BR2_PACKAGE_CAIRO_PNG
 
 config BR2_PACKAGE_CAIRO_SVG
 	bool "svg support"

package/cairo/cairo.mk

@@ -86,7 +86,6 @@ endif
 
 ifeq ($(BR2_PACKAGE_CAIRO_SCRIPT),y)
 	CAIRO_CONF_OPT += --enable-script
-	CAIRO_DEPENDENCIES += zlib
 else
 	CAIRO_CONF_OPT += --disable-script
 endif