The Embedded Android build (Boot to Qt Android injection) is defined by
having both Q_OS_ANDROID and Q_OS_ANDROID_EMBEDDED flags defined,
as well as having Qt config android-embedded.
Those flags are set in mkspecs when building for embedded Android.
This commit enables the possibility to build embedded Android builds.
(i.e. Qt build for Android baselayer only, without JNI)

Change-Id: I8d139b6d7b61c00ad44079cbfa6e5c77e8618a7b
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>