[cc2538] fix a typo in energy scan (#5748)
[cc2538] fix a typo in energy scan (#5748)


srickardti/openthread,openthread/openthread,jwhui/openthread,openthread/openthread,chshu/openthread,chshu/openthread,chshu/openthread,chshu/openthread,openthread/openthread,jwhui/openthread,abtink/openthread,chshu/openthread,jwhui/openthread,abtink/openthread,abtink/openthread,openthread/openthread,bukepo/openthread,bukepo/openthread,bukepo/openthread,abtink/openthread,bukepo/openthread,srickardti/openthread,jwhui/openthread,srickardti/openthread,srickardti/openthread,chshu/openthread