fdt: make fdt_get_base_address() return OF_BAD_ADDR when "reg" not found

Currently, fdt_get_base_address() returns 0 if the "reg" property is
missing. Since 0 is a valid value, it is not suitable for the error
handling. Return OF_BAD_ADDR instead.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/common/fdt_support.c b/common/fdt_support.c
index a23367b..699d4a2 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -1552,7 +1552,7 @@
 
 	prop = fdt_getprop(fdt, node, "reg", &size);
 
-	return prop ? fdt_translate_address(fdt, node, prop) : 0;
+	return prop ? fdt_translate_address(fdt, node, prop) : OF_BAD_ADDR;
 }
 
 /*