[dts] [dts 5/6] test_plans/ptpclient_test_plan: update test plan to sync with testcase

[lingwei]

Signed-off-by: lingwei <weix.ling at intel.com>
---
 test_plans/ptpclient_test_plan.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test_plans/ptpclient_test_plan.rst b/test_plans/ptpclient_test_plan.rst
index 64f3faa..7781bff 100644
--- a/test_plans/ptpclient_test_plan.rst
+++ b/test_plans/ptpclient_test_plan.rst
@@ -44,6 +44,9 @@ Prerequisites
 Assume one port is connected to the tester and "linuxptp.x86_64"
 has been installed on the tester.
 
+Case Config::
+    For support IEEE1588, need to set "CONFIG_RTE_LIBRTE_IEEE1588=y" in ./config/common_base and re-build DPDK.
+
 The sample should be validated on Forville, Niantic and i350 Nics. 
 
 Test case: ptp client
-- 
2.17.1