dns/dnsmasq-devel: update to v2.87test8

new CHANGELOG entries since test7:

- Fix problem with binding DHCP sockets to an individual interface.
  Despite the fact that the system call tales the interface _name_ as a
  parameter, it actually, binds the socket to interface _index_.
  Deleting the interface and creating a new one with the same name
  leaves the socket bound to the old index. (Creating new sockets always
  allocates a fresh index, they are not reused). We now take this
  behaviour into account and keep up with changing indexes.

- Add --conf-script configuration option.