usbtinyisp source code update for modern AVR GCC

For those besides me who have downloaded the source code to the USB Tiny from AdaFruit, you'll note that on the download page it says you must use gcc-3.4.6 to build it. That's an antique.

I started down the road of patching the code so that it can be compiled by a modern AVR GCC and libc, but eventually discovered that someone had already done it.

I then went on to find the original home of the code. He has a 1.7 version of the code, but the pin assignments are different. The following patch makes it work with the USB µISP up through the current version (0.4) (it should also work with the original AdaFruit USBTiny and the SparkFun pocket AVR programmer):

EDIT: Turns out the patch was unnecessary... I was trying to build from the 'spi' directory, but the correct place is the 'usbtinyisp' directory. That has the correct pin assignments and requires no modifications. Just 'make' and reflash. Joy!