selftests/tcp_ao: Fix fscanf() call for format-security

On my new laptop with packages from nixos-unstable, gcc 12.3.0 produces:
> lib/proc.c: In function ‘netstat_read_type’:
> lib/proc.c:89:9: error: format not a string literal and no format arguments [-Werror=format-security]
> 89 | if (fscanf(fnetstat, type->header_name) == EOF)
> | ^~
> cc1: some warnings being treated as errors

Here the selftests lib parses header name, while expectes non-space word
ending with a column.

Fixes: cfbab37b3da0 ("selftests/net: Add TCP-AO library")
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests/net: Fix various spelling mistakes in TCP-AO tests

There are a handful of spelling mistakes in test messages in the
TCP-AIO selftests. Fix these.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests/net: Add TCP-AO library

Provide functions to create selftests dedicated to TCP-AO.
They can run in parallel, as they use temporary net namespaces.
They can be very specific to the feature being tested.
This will allow to create a lot of TCP-AO tests, without complicating
one binary with many --options and to create scenarios, that are
hard to put in bash script that uses one binary.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>