xtensa: support default device tree buses

This currently includes simple-bus.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index d21bfa7..f38bade 100644
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -239,7 +239,7 @@
 
 static int __init xtensa_device_probe(void)
 {
-	of_platform_populate(NULL, NULL, NULL, NULL);
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 	return 0;
 }