Update README.md documentation

Added:
    - Secure boot test section

Change-Id: I351f287a6ced84c19e1052951971a07bba4da9aa
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/README.md b/README.md
index acd1152..d3b4df5 100755
--- a/README.md
+++ b/README.md
@@ -20,6 +20,7 @@
 * RAS (Reliability, availability and serviceability)
 * Web UI testing
 * IO storage and EEH (Enhanced Error Handling) testing
+* Secure boot
 
 **Debugging Supported List**
 * SOL collection
@@ -94,6 +95,9 @@
 
 `mnfg/`: Contains test cases for factory reset (DHCP mode) and PGOOD testing.
 
+`secureboot/`: Contains test cases for secure boot testing on a secure boot
+               feature enabled system only.
+
 `tools/`: Contains various tools.
 
 `templates/`: Contains sample code examples and setup testing.