remote-access: only offer our key when initiating connection

Unless we use "IdentitiesOnly" option ssh client will try any and all
ssh keys offered by ssh agent, which causes SSH server to abort
handshake due to too many authorization failures.

BUG=None
TEST=Make sure that "cros flash <IP> image.bin" works even if one has
     several keys (5 or more) served by the ssh-agent (check ssh-add -L)

Change-Id: I216a346b2893a4afb8607b0472bd019caa65235c
Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/372022
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed