Remove useless maxadmin commands

The commands did nothing.

server/core/dcb.c

@@ -1915,16 +1915,6 @@ dprintOneDCB(DCB *pdcb, DCB *dcb)
     }
 }
 
-/*
- * @brief Print DCB list statistics
- *
- * @param       pdcb    DCB to print results to
- */
-void
-dprintDCBList(DCB *pdcb)
-{
-}
-
 /**
  * Diagnostic to print all DCB allocated in the system
  *

server/core/poll.c

@@ -1522,17 +1522,6 @@ void poll_fake_hangup_event(DCB *dcb)
     poll_add_event_to_dcb(dcb, NULL, ev);
 }
 
-/**
- * Print the event queue contents
- *
- * @param pdcb          The DCB to print the event queue to
- */
-void
-dShowEventQ(DCB *pdcb)
-{
-}
-
-
 /**
  * Print the event queue statistics
  *

server/core/session.c

@@ -460,16 +460,6 @@ printAllSessions()
     dcb_foreach(printAllSessions_cb, NULL);
 }
 
-/*
- * @brief Print session list statistics
- *
- * @param       pdcb    DCB to print results to
- */
-void
-dprintSessionList(DCB *pdcb)
-{
-}
-
 /** Callback for dprintAllSessions */
 bool dprintAllSessions_cb(DCB *dcb, void *data)
 {