Allow connection to self when impersonator set
If the target of a context establishment is the impersonator itself,
then allow it. This kind of context establishment is used by tools like
mod_auth_gssapi to be able to inspect the ticket just obtained via
impersonation and it is basically a noop as the acceptor and the
impersonator are the same entitiy.
Signed-off-by: Simo Sorce <firstname.lastname@example.org>
Reviewed-by: Robbie Harwood <email@example.com>