Setting up the .data and .bss section happens in arm7_init.c now.
The code was commented out anyway, so just remove it.
Also remove leftover variable declarations that were only used in
the dead code.
- split up interrupt vector code from bootloader.c to vectors.c
- moved bootloader.c to arm7_init.c
- Use consistent naming:
- use lower case for everything but preprocessor stuff
- ISRs now named isr_foo()