bind: Update to 9.16.40

bind: Update to 9.16.40

For details  see:
https://downloads.isc.org/isc/bind9/9.16.40/doc/arm/html/notes.html#notes-for-bind-9-16-40

"Notes for BIND 9.16.40
Bug Fixes

    Logfiles using timestamp-style suffixes were not always correctly
    removed when the number of files exceeded the limit set by versions.
    This has been fixed for configurations which do not explicitly specify
    a directory path as part of the file argument in the channel
    specification. [GL #3959] [GL #3991]

    Performance of DNSSEC validation in zones with many DNSKEY records has
    been improved. [GL #3981]"

Signed-off-by: Matthias Fischer <matthias.fischer@ipfire.org>
Reviewed-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>