openssh: sync with upstream's default

openssh: sync with upstream's default

This change sync the contents of this file with upstream's
ssh_config except for the locally added line
'Include /etc/ssh/ssh_config.d/*.conf'.

More specifically the ForwardXXX options are disabled by default,
this sync with what ssh_config(5) says about these two items.

In addition, the RSAAuthentication items are removed as they are v1 protocol.
See the contents of Changelog file in openssh project as below:
"""
commit bfe19197a92b7916f64a121fbd3c179abf15e218
Author: Darren Tucker <dtucker@dtucker.net>
Date:   Fri Jul 2 15:43:28 2021 +1000

    Remove now-unused SSHv1 enums.

    sRhostsRSAAuthentication and sRSAAuthentication are protocol 1 options
    and are no longer used.
"""

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>