- mkerrors.sh: Included several termios-related constants that were
  missing. Also included definitions of tty-related ioctl numbers for
  linux.

- zerrors_linux_*: the files have been generated using
  "./mkerrors.sh". After their automatic generation the files have
  been manually edited to remove changes that were not due to this
  patch.

Change-Id: I0463112542a5c1c41583007003b652375f9ce572
Reviewed-on: https://go-review.googlesource.com/17184Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>