tcpsso: remove support for some IPPROTO_TCP-level socket option names

Remove support for IPPROTO_TCP-level socket option names, because these
names will be removed from the source tree soon.
The corresponding socket options are not implemented by the TCP stack
at all.
This change was suggested by Peter Lei.

Reviewed by: cc
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D46437