selftests: net: add ipv6 ping to local address from localhost

Test ipv6 pinging to local configured address and linklocal address from
localhost with -I ::1.

Signed-off-by: Fernando Fernandez Mancera <[e-mail]>
Reviewed-by: David Ahern <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

tools/testing/selftests/net/fcnal-test.sh

···
 		log_test_addr ${a} $? 2 "ping local, device bind"
 	done
 
+	for a in ${NSA_LO_IP6} ${NSA_LINKIP6}%${NSA_DEV} ${NSA_IP6}
+	do
+		log_start
+		run_cmd ${ping6} -c1 -w1 -I ::1 ${a}
+		log_test_addr ${a} $? 0 "ping local, from localhost"
+	done
+
 	#
 	# ip rule blocks address
 	#