bind: bump to version 9.10.3-P2

Leave the LTS series for the latest stable version for libressl
compatibility.
Unfortunately this means threads are now required, but this shouldn't be
a problem for a fully-featured resolver.

Drop 0001-disable-tests.patch since it's no longer required, genrandom
isn't run unless the tests are called upon.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>