The main reason for upgrading of the Qt version is the hunt for a broken
BT/BLE stack, preventing downloads from BT/BLE enabled DCs, in relation
to arm64 architecture builds. (And the absolute need for an arm64 build
in relation to the publication of the Android app in Googles Play
store).
In addition, Qt 5.12.4 starts supporting OpenSSL 1.1.1c, and trying to
use our current OpenSSL 1.0 series is highly discouraged by Qt (and
OpenSSL itself).
So, upgrade both in unison. But ... be careful bisecting issues on this
commit, as it does break our build. That will be fixed in the next
commit.
This fixes the BT/BLE download for arm64!
Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>