Working on differences from 7.3 to 7.5 version

FossilOrigin-Name: 02bf967f2dfcb1349d8c843daab6b16ac998a5b857ffb4ee71d7e84f44313ef8

src/mod/capwap/capwap_actions_ac.c

@@ -535,6 +535,7 @@ static struct cw_ElemDef echo_request_elements[] ={
 
 static int echo_response_states[] = {CAPWAP_STATE_RUN,0};
 static struct cw_ElemDef echo_response_elements[] ={
+	{0,0,CAPWAP_ELEM_VENDOR_SPECIFIC_PAYLOAD,	0, CW_IGNORE},
 	{0,0,0,0,0}
 };