avrdude: new package

[Thomas:
 - remove empty newline at the end of Config.in
 - use lowercase for the package name in the comment header
 - reword the comment explaining why autoreconf is needed
 - add optional dependency on libftdi, which avrdude can use
 - remove avrdude.conf.bak file from /etc]

Signed-off-by: Wojciech M. Zabolotny <wzab01@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>