appletvos: Resolve "The CXX compiler identification is unknown" error

I'm unsure if the MACOSX_BUNDLE_GUI_IDENTIFIER bundle identifier should me made configurable from the toolchain file. I can remember that in the past provisioning profiles were (/ could be) issued for org.example.*. If we now just use the generated try_compile name as an identifier, it might result in an unsuccessful profile lookup.

For now, at least allow developers to set the development team and use a more suitable product type to allow tvOS builds to be set up more easily from toolchain files.

Topic-rename: 16839-better-tvos-support Fixes: #16839 (closed)