tools/image-host: fix sign-images bug

property "sign-images" is never found, fix this.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/image-host.c b/tools/image-host.c
index 0d5c88c..8e185ec 100644
--- a/tools/image-host.c
+++ b/tools/image-host.c
@@ -403,7 +403,7 @@
 		goto err_mem;
 
 	/* Get a list of images that we intend to sign */
-	prop = fit_config_get_image_list(fit, conf_noffset, &len,
+	prop = fit_config_get_image_list(fit, sig_offset, &len,
 					&allow_missing);
 	if (!prop)
 		return 0;