Tools: document IE24 and IEFC log messages

Author: peterbarker

Tools/autotest/vehicle_test_suite.py

@@ -3093,8 +3093,6 @@ def LoggerDocumentation_greylist(self):
         are currently known as undocumented'''
         return set([
             "FTN3",  # gyrofft
-            "IE24",  # generator
-            "IEFC",  # generator
             "SBRE",  # septentrio
 
             "SAF1",  # blimp-sim