GitLab

- replace the hand written serial input flush routine with the termios one.
- serialport_discard_read isn't necessary anymore - it just wrapped
  sp_flush_incoming with no extra value.
- serialport_read and serialport_write would misbehave if read or write
  didn't process everything in one go.
- sp_flush_incoming should be #define'd out for FAKE_COMMUNICATION like
  serialport_discard_read was

Corresponding to flashrom svn r831.
Signed-off-by: Patrick Georgi <patrick.georgi@coresystems.de>
Acked-by: Sean Nelson <audiohacked@gmail.com>