image: fix support for Android boot images with no ramdisk

If an Android boot image does not contain a ramdisk, make sure rd_len
and rd_data are returned to indicate no ramdisk rather than just relying
on returning an error.

Signed-off-by: Rob Herring <robh@kernel.org>

common/image-android.c

@@ -130,8 +130,10 @@ ulong android_image_get_kload(const struct andr_img_hdr *hdr)
 int android_image_get_ramdisk(const struct andr_img_hdr *hdr,
 			      ulong *rd_data, ulong *rd_len)
 {
-	if (!hdr->ramdisk_size)
+	if (!hdr->ramdisk_size) {
+		*rd_data = *rd_len = 0;
 		return -1;
+	}
 
 	printf("RAM disk load addr 0x%08x size %u KiB\n",
 	       hdr->ramdisk_addr, DIV_ROUND_UP(hdr->ramdisk_size, 1024));