dnsmasq: move to meta-networking and tweak

* Make dbus a PACKAGECONFIG option and remove dnsmasq-dbus recipe
* Set LICENSE to correctly indicate choice of licenses
* Set SUMMARY instead of DESCRIPTION

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>