software node: Correct a OOB check in software_node_get_reference_args()

software_node_get_reference_args() wants to get @index-th element, so
the property value requires at least '(index + 1) * sizeof(*ref)' bytes
but that can not be guaranteed by current OOB check, and may cause OOB
for malformed property.

Fix by using as OOB check '((index + 1) * sizeof(*ref) > prop->length)'.

Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/20250414-fix_swnode-v2-1-9c9e6ae11eab@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Zijun Hu

drivers/base/swnode.c

@@ -529,7 +529,7 @@ software_node_get_reference_args(const struct fwnode_handle *fwnode,
 	if (prop->is_inline)
 		return -EINVAL;
 
-	if (index * sizeof(*ref) >= prop->length)
+	if ((index + 1) * sizeof(*ref) > prop->length)
 		return -ENOENT;
 
 	ref_array = prop->pointer;