string_view is available with both boost and std.

Backported extra patch getting rid of using namespace std.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

Update dnsdist to next major release 1.4.0. This release introduces
dependencies on libh2o-evloop and libwslay for support of DNS over
HTTPS.

Release Blog Post: https://blog.powerdns.com/2019/11/20/dnsdist-1-4-0/
Changelog: https://dnsdist.org/changelog.html#change-1.4.0

Also removes compatibility patches required for previous release that have
been incorporated upstream.

Signed-off-by: James Taylor <james@jtaylor.id.au>

Add patch that detects when -latomic is needed.

Fix compilation without deprecated OpenSSL APIs.

Hard-code lua to avoid luajit dependency.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

Maintainer: me
Compile tested: armv7l, OpenWRT SDK
Run tested: armv7l  Linksys WRT1900ACS, OpenWrt SNAPSHOT, r9987-655fff1571 -
confirmed dnsdist links correctly against dependencies and doesn't experience
errors at run-time when enabling features.

Description:
dnsdist is a highly DNS-, DoS- and abuse-aware loadbalancer. Its goal in life is
to route traffic to the best server, delivering top performance to legitimate
users while shunting or blocking abusive traffic.

dnsdist is dynamic, its configuration language is Lua and it can be changed at
runtime, and its statistics can be queried from a console-like interface or an
HTTP API.

https://dnsdist.org/

Closes: PowerDNS/pdns#3294

Signed-off-by: James Taylor <james@jtaylor.id.au>