gdk-pixbuf: Fix the native png load error and remove duplicated recipe
Native gdk-pixbuf-csource failed to load png file as the "loaders.cache" was
not properly set by gdk-pxibuf-query-loaders when install. This patch use the
wrapper script rather than query-loaders binary as required libtool library was
not installed when do_install_append.
Also remove dedicated recipe for gdk-pixbuf-native.
