avr linkerscript
================

Starting from avr-binutils 2.26, the linker defines symbol that can be
overridden to configure ROM and RAM length.

This ldscript is used for supporting older versions on avr-binutils like on
ubuntu xenial.

Generated by extracting the output of

    avr-gcc -Wl,--verbose -mmcu=$(CPU)

With avr-binutils 2.26
