When in ra server mode, configure nameservers passed in router
announcements from the dns value (which is already used by odhcpd).
This also fixes FS#677 by using the global IPv6 address of the router
instead of the link local address (if no nameservers are configured).
Signed-off-by: Arjen de Korte <build+lede@de-korte.org>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com> [PKG_RELEASE increase]
070a46121d