Fix table format in README.md

Github flavored markdown requires a blank line between text and table.

Change-Id: I55d6b964b9fb699e7b7a57cbd3b8f7b54a617947
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/README.md b/README.md
index 9584ca7..74f58bf 100644
--- a/README.md
+++ b/README.md
@@ -49,6 +49,7 @@
    * BOTH: Both BMC and Host can set the time.
 
 A summary of which cases the time can be set on BMC or HOST:
+
 Mode      | Owner | Set BMC Time  | Set Host Time
 --------- | ----- | ------------- | -------------------
 NTP       | BMC   | Fail to set   | Not allowed