Incomplete information in docs

http://doc.qt.io/qt-5/opensslsupport.html
does not mention two important steps
a) it is important to work with openssl LTS version 1.0.x , exactly the version https://www.openssl.org/source/openssl-10.2j.tar.gz worked for me. Newer ones did not.
b) it is necessary to set environment variable SYS_CROSSROOT into NDK folder, otherwise you get cryptic error meaning you build for your local host, not cross-platform
export CROSS_SYSROOT=~/fun/android-ndk-r12b/platforms/android-23/arch-arm

I think it is worth mentioning that OpenSSL bundling is necessary for Android 6.0+ - as described in https://geonet.esri.com/community/developers/native-app-developers/arcgis-runtime-sdk-for-qt/blog/2016/08/12/announcement-for-qt-developers-targeting-android-60

Otherwise https:// connection stop working