JSON: Correcting bad sensor names

Signed-off-by: malikabh <abhishek.malik@intel.com>

src/emg/emg.json

@@ -3,7 +3,7 @@
     "Description": "Grove EMG Muscle Signal Reader Library",
     "Sensor Class":
     {
-        "emg":
+        "EMG":
         {
             "Name": "Electromyography (EMG) Sensor",
             "Description": "Grove EMG muscle signal reader gathers small muscle signals, then processes them, and returns the result.",
@@ -35,4 +35,4 @@
             }
         }
     }
-}
+}