example: actually chmod new resolv.conf after overwriting

Signed-off-by: Steven Barth <steven@midlink.org>

odhcp6c-example-script.sh

@@ -12,6 +12,7 @@ update_resolv() {
 			echo "nameserver $c #odhcp6c:$device:" >> /tmp/resolv.conf.tmp
 		done
 		mv /tmp/resolv.conf.tmp /etc/resolv.conf
+		chmod 0644 /etc/resolv.conf
 	) 9>/tmp/resolv.conf.lock
 	rm -f /tmp/resolv.conf.lock /tmp/resolv.conf.tmp
 }