etc/dists/scripts/set_dns.sh: improve removing old nameservers

Previous sed expression was removing any line with 'nameserver' in it
(and .* at the end was unnecessary). This includes comments and so on.

This grep expression only filters out lines where nameserver is a separate
word at the beginning of a line.

Signed-off-by: Kir Kolyshkin <kir@openvz.org>
1 file changed