Merge branch 'bpf: net: Remove duplicated code from bpf_getsockopt()'

Martin KaFai Lau says:

====================

From: Martin KaFai Lau <martin.lau@kernel.org>

The earlier commits [0] removed duplicated code from bpf_setsockopt().
This series is to remove duplicated code from bpf_getsockopt().

Unlike the setsockopt() which had already changed to take
the sockptr_t argument, the same has not been done to
getsockopt().  This is the extra step being done in this
series.

[0]: https://lore.kernel.org/all/20220817061704.4174272-1-kafai@fb.com/

v2:
- The previous v2 did not reach the list. It is a resend.
- Add comments on bpf_getsockopt() should not free
  the saved_syn (Stanislav)
- Explicitly null-terminate the tcp-cc name (Stanislav)
====================

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>