[SeaBIOS] BootDevice description cut off

[Rene Shuster]

Please change line 485 of src/boot.c and increase the BootDevice
description length 'char desc' value from [60] to [80]. Right now it's
cutting off text for some devices. 80 would most likely fix the issue and
provide enough space for very lengthy descriptions. Example shown here:
https://github.com/coreboot/seabios/pull/1
Thanks.