[mle] remove unused MleRouter::RemoveNeighbor method (#3926)

src/core/thread/mle_router.cpp

@@ -3123,18 +3123,6 @@ bool MleRouter::IsMinimalChild(uint16_t aRloc16)
     return rval;
 }
 
-otError MleRouter::RemoveNeighbor(const Mac::Address &aAddress)
-{
-    otError   error = OT_ERROR_NONE;
-    Neighbor *neighbor;
-
-    VerifyOrExit((neighbor = GetNeighbor(aAddress)) != NULL, error = OT_ERROR_NOT_FOUND);
-    RemoveNeighbor(*neighbor);
-
-exit:
-    return error;
-}
-
 void MleRouter::RemoveNeighbor(Neighbor &aNeighbor)
 {
     switch (mRole)

src/core/thread/mle_router_ftd.hpp

@@ -316,17 +316,6 @@ public:
      */
     void SetRouterDowngradeThreshold(uint8_t aThreshold) { mRouterDowngradeThreshold = aThreshold; }
 
-    /**
-     * This method removes a link to a neighbor.
-     *
-     * @param[in]  aAddress  The link address of the neighbor.
-     *
-     * @retval OT_ERROR_NONE       Successfully removed the neighbor.
-     * @retval OT_ERROR_NOT_FOUND  Could not find the neighbor.
-     *
-     */
-    otError RemoveNeighbor(const Mac::Address &aAddress);
-
     /**
      * This method removes a link to a neighbor.
      *

src/core/thread/mle_router_mtd.hpp

@@ -81,7 +81,6 @@ public:
     uint8_t GetLinkCost(uint16_t) { return 0; }
     uint8_t GetCost(uint16_t) { return 0; }
 
-    otError RemoveNeighbor(const Mac::Address &) { return BecomeDetached(); }
     otError RemoveNeighbor(Neighbor &) { return BecomeDetached(); }
 
     bool IsMinimalChild(uint16_t) const { return false; }