Some compiler is brain-damaged that it will yeild a warning for headers
not ended with a newline. Yes, I mean you, Keil.

M0 core is always booted by the M4 core. It means that if we are running
in M0, the clock is always configured.

Before the project was established with RB_ROOT

Before the project is generated by rtt_root

    1. adapt to M052xDN/xDE, M054xDN/xDE, M058xDN/xDE, M0516/xDN/xDE.
    2. support heap memory management.