selftests: mptcp: set addr id for removing testcases

The removing testcases can only delete the addresses from id 1, this
patch added the support for deleting the addresses from any id that user
set.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/mptcp/mptcp_join.sh

@@ -284,14 +284,19 @@ do_transfer()
 		let rm_nr_ns1=-addr_nr_ns1
 		if [ $rm_nr_ns1 -lt 8 ]; then
 			counter=1
+			dump=(`ip netns exec ${listener_ns} ./pm_nl_ctl dump`)
+			if [ ${#dump[@]} -gt 0 ]; then
+				id=${dump[1]}
 				sleep 1
 
 				while [ $counter -le $rm_nr_ns1 ]
 				do
-				ip netns exec ${listener_ns} ./pm_nl_ctl del $counter
+					ip netns exec ${listener_ns} ./pm_nl_ctl del $id
 					sleep 1
 					let counter+=1
+					let id+=1
 				done
+			fi
 		else
 			sleep 1
 			ip netns exec ${listener_ns} ./pm_nl_ctl flush
@@ -318,14 +323,19 @@ do_transfer()
 		let rm_nr_ns2=-addr_nr_ns2
 		if [ $rm_nr_ns2 -lt 8 ]; then
 			counter=1
+			dump=(`ip netns exec ${connector_ns} ./pm_nl_ctl dump`)
+			if [ ${#dump[@]} -gt 0 ]; then
+				id=${dump[1]}
 				sleep 1
 
 				while [ $counter -le $rm_nr_ns2 ]
 				do
-				ip netns exec ${connector_ns} ./pm_nl_ctl del $counter
+					ip netns exec ${connector_ns} ./pm_nl_ctl del $id
 					sleep 1
 					let counter+=1
+					let id+=1
 				done
+			fi
 		else
 			sleep 1
 			ip netns exec ${connector_ns} ./pm_nl_ctl flush