Check for langinfo.h presence for smb_utils

OS like Android don't have langinfo.h, so assume it is UTF-8

Signed-off-by: Julien 'Lta' BALLET <contact@lta.io>
Debug: avoid warnings when in release mode

Signed-off-by: Julien 'Lta' BALLET <contact@lta.io>
smb_ntlm: fix warnings

Signed-off-by: Julien 'Lta' BALLET <contact@lta.io>