dts: Fix OF_LIVE dependency

lib/of_live.c references the following 2 ofnode APIs:
of_alias_scan() and of_get_property().

These APIs get built only when DM is on. Fix the dependency then.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

dts/Kconfig

@@ -60,7 +60,7 @@ config TPL_OF_CONTROL
 
 config OF_LIVE
 	bool "Enable use of a live tree"
-	depends on OF_CONTROL
+	depends on DM && OF_CONTROL
 	help
 	  Normally U-Boot uses a flat device tree which saves space and
 	  avoids the need to unpack the tree before use. However a flat