The default terminal setting for a new pty on Linux (unix98) has +ONLCR,
resulting in '\n' writes by a container process to be converted to
'\r\n' reads by the managing process. This is quite unexpected, and
causes multiple issues with things like bats testing. To fix it, make
the terminal sane after opening it by setting -ONLCR.
This patch might need to be rewritten after the console rewrite patchset
is merged.
Signed-off-by: Aleksa Sarai <asarai@suse.de>