AVR-LibC 2.2.1 released

Release 2.2.1 is a quick followup on 2.2.0.

The major reason for rolling this release was to include a check in the configure script that ensures a compatible version of binutils is present.

When used with GNU binutils older than v2.40, overflows of the data region may not be diagnosed.

AVR-LibC 2.2.0 released

This is the first version of the AVR-LibC project that is released from Github.

Relevant part of the NEWS file:

https://github.com/avrdudes/avr-libc/blob/16b742119eaed8d966929033b1ad325faea89798/NEWS#L1-L179

IMPORTANT:

This release requires GNU Binutils with at least version 2.40. Earlier versions cause the wrong address for the data being used on many devices, resulting in linker complaints that the data do not fit. See issue #971.