- atusb.c (main), board.h (board_init), board.c (board_init): moved
clock and I/O initialization to board file
- board.h (led), board.c (led), atusb.c (main): abstracted LED setting
in function "led" instead of open-coding it
- spi.c (spi_init): set nSS to 1 before enabling the output, so that we
don't generate what looks like an empty SPI transaction
- board.h (read_irq), board.c: return status of the RF IRQ
- board.h (PIN, PIN_1, PIN_2): macros to read port pins
- ep0.c (my_setup): make ATUSB_POLL_INT return the real interrupt
- 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
