Bug#271145: termwrap has inconsistent behaviour on serial terminal

[Ognyan Kulev <ogi@fmi.uni-sofia.bg>]

Package: base-config
Version: 2.44
Tags: d-i

When terminal is serial console, termwrap behaves differently depending 
on the charset:

try_load_charset (most charsets) emits error and calls unset_lang_language.

With UTF-8, eucJP, EUC-JP and KOI8-R termwrap does nothing, i.e. it 
expects that the serial console already supports the charset.

Regards,
ogi