x/crypto/ssh/terminal: replace \n with \r\n.

18e6eb769a6 made MakeRaw match C's behaviour. This included clearing the
OPOST flag, which means that one now needs to write \r\n for a newline,
otherwise the cursor doesn't move back to the beginning and the terminal
prints a staircase.

(Dear god, we're still emulating line printers.)

This change causes the terminal package to do the required

Fixes golang/go#17364.

Change-Id: Ida15d3cf701a21eaa59161ab61b3ed4dee2ded46
Reviewed-on: https://go-review.googlesource.com/33902
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2 files changed