mgmt+tools: rename 'datas' to 'data'

Plural form of 'data' is 'data'.

refs #3955

Change-Id: I62f5ebe53b8e36d565e5a243288eb12ae9a08014
diff --git a/daemon/mgmt/face-manager.cpp b/daemon/mgmt/face-manager.cpp
index d9b2a03..4cc3288 100644
--- a/daemon/mgmt/face-manager.cpp
+++ b/daemon/mgmt/face-manager.cpp
@@ -394,8 +394,8 @@
   const face::FaceCounters& counters = face.getCounters();
   status.setNInInterests(counters.nInInterests)
         .setNOutInterests(counters.nOutInterests)
-        .setNInDatas(counters.nInData)
-        .setNOutDatas(counters.nOutData)
+        .setNInData(counters.nInData)
+        .setNOutData(counters.nOutData)
         .setNInNacks(counters.nInNacks)
         .setNOutNacks(counters.nOutNacks)
         .setNInBytes(counters.nInBytes)