[VOL-2043] : OLT Enable Test Case

- Added more test cases for OLT Enable. Now covers all scenarios.
- Fixed typos in unit test README.md

Change-Id: Ib931d89cedee78fe40ca67761a028365a047ebc3
diff --git a/agent/test/src/bal_mocker.cc b/agent/test/src/bal_mocker.cc
index 5c89b03..b38906f 100644
--- a/agent/test/src/bal_mocker.cc
+++ b/agent/test/src/bal_mocker.cc
@@ -18,7 +18,8 @@
 
 
 #include "bal_mocker.h"
-
+extern "C" {
 CMOCK_MOCK_FUNCTION1(BalMocker, bcmolt_host_init, bcmos_errno(bcmolt_host_init_parms*));
 CMOCK_MOCK_FUNCTION2(BalMocker, bcmolt_cfg_get, bcmos_errno(bcmolt_oltid, bcmolt_cfg*));
 CMOCK_MOCK_FUNCTION2(BalMocker, bcmolt_oper_submit, bcmos_errno(bcmolt_oltid, bcmolt_oper*));
+}