The Makefile didn't see the FreakUSB object files at the expected place,
so it always rebuild them.
- Makefile (USB_OBJS): removed paths from object file names
- Makefile: added vpaths for the FreakUSB source file locations
- Makefile (atusb.elf, clean): we no longer need $(notdir ...) for the
object files
- io.h: renamed to board.h
- Makefile (OBJS): added board.o
- atusb.c (reset_rf): moved to board.c
- board.h (reset_rf): give reset_rf a proper declaration
- atusb.c, ep.c, spi.c: include board.h instead of io.h
- Makefile (OBJS): added spi.o
- spi.h, spi.c, atusb.c: moved SPI functions to new file
- spi.h (spi), spi.c (spi), atusb.c (main): renamed function "spi" to
"spi_io"
- atusb.c (reset_rf, main): moved transceiver reset to separate function
- ./: basic framework to build a firmware that can enumerate
- usb/patches/: patches to make FreakUSB 0.7 compile cleanly and to make
it work in our context
