tools: kwboot: Fix initialization of tty device

Explicitly disable 2 stop bits by clearing CSTOPB flag, disable modem
control flow by clearing CRTSCTS flag and do not send hangup after closing
device by clearing HUPCL flag.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
1 file changed