- Mention that Android Studio's JDK can be used
- Fix duplicate "Building Qt" titles so they can be linked to properly
- Fix typos in qdoc commands
- Fix configure command issues:
  - Move make flags out
  - Change android-g++ to android-clang
  - Expand ANDROID_NDK_PATH and ANDROID_NDK_ROOT variables

Task-number: QTCREATORBUG-22626
Change-Id: Iefe9d21ad9b06f792e7c20fb4698c00fa4b24c2a
Reviewed-by: Kavindra Palaraja <kpalaraja@luxoft.com>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>