BUG/MEDIUM: fd: Use the provided tgid in fd_insert() to get tgroup_info

BUG/MEDIUM: fd: Use the provided tgid in fd_insert() to get tgroup_info

In fd_insert(), use the provided tgid to ghet the thread group info,
instead of using the one of the current thread, as we may call
fd_insert() from a thread of another thread group, that will happen at
least when binding the listeners. Otherwise we'd end up accessing the
thread mask containing enabled thread of the wrong thread group, which
can lead to crashes if we're binding on threads not present in the
thread group.
This should fix Github issue #2991.

This should be backported up to 2.8.