When building uORB for NuttX flat build, or for some other target, everything
works as before.
When building uORB for NuttX protected or kernel build, this does the following:
- The kernel side uORB library reigsters a boardctl handler for calls from userspace
and services the boardctl_ioctls by calling the actual uORB functions
- For user mode binaries, the uORBManager acts as a proxy, making boardctl_ioctl calls to the
kernel side
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>