Android debugger requires default NDK

When using a single NDK and not having any defaults set:

Starting a debugger could result in error messages that are hard to understand:

/nativeloader: Load libjdwp.so using system ns (caller=<unknown>): ok

I/System.out: Debugger has connected

I/System.out: waiting for debugger to settle...

I/System.out: waiting for debugger to settle...

16:29:39: Cannot find C++ debug server in NDK installation.

The lldb-server binary has not been found.

16:29:39: Android target "org.qtproject.grpc.chat" died. 

The lldb-server could not be found since without a default "something" gets chosen for you:

You would need to debug qtcreator to find that.

I think the error message could be improved to show the actual path that is looked for and more importantly, I think when having a single ndk in the android settings this should become the default.