be: fix with filtered bufferevents and connect() without EAGAIN

be: fix with filtered bufferevents and connect() without EAGAIN

With filtered bufferevents (i.e. not real one, that have socket), we can
trigger incorrect callback in this case. Let's look at example with http
and bufferevent_openssl_filter_new():
- bev = bufferevent_openssl_filter_new()
- http layer trying to connect() to localhost with bev
  # at this time, bev have writecb/readcb NULL but ev_write/ev_read has
  # timeout with 45 secs, default HTTP connect timeout
- and when connect() retruns without EAGAIN (BSD'ism) we called
  event_active() before (with EV_WRITE), and this will call ev_write
  timeout only, while it is more correct to act on bufferevent instead
  of plain event, so let's trigger EV_WRITE for bufferevent which will
  do the job (and let's do this deferred).

Fixes: http/https_simple # under solaris