tools: mkimage: Avoid ENODATA in host tools

ENODATA isn't part of POSIX.  Use EINVAL instead.

Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/tools/image-host.c b/tools/image-host.c
index ab6f756..698adfb 100644
--- a/tools/image-host.c
+++ b/tools/image-host.c
@@ -1205,7 +1205,7 @@
 		if (!key_name)
 			printf("The property key-name is missing in the node %s\n",
 			       IMAGE_PRE_LOAD_PATH);
-		ret = -ENODATA;
+		ret = -EINVAL;
 		goto out;
 	}