sockets: on accept(2) don't copy all of so_options to new socket
As uncovered by e3ba0d6adde3 we are copying lots of irrelevant options
from the listener to an accepted socket, even those that aren't relevant
to a non-listener, e.g. SO_REUSE*, SO_ACCEPTFILTER. Stop doing that
and provide a fixed opt-in list for options to be inherited. Ideally
we shall not inherit anything at all. For compatibility inherit a set
of options that are meaningful for a non-listening socket of a protocol
that can listen(2).
Differential Revision: https://reviews.freebsd.org/D41412
Fixes: e3ba0d6adde3c694f46a30b3b67eba43a7099395