be_openssl: Fix writing into filted openssl bufferevent after connected

be_openssl: Fix writing into filted openssl bufferevent after connected

The main problems was due to when bufferevent_openssl has underlying (i.e.
created with bufferevent_openssl_filter_new()) some events was
disabled/suspended, while with openssl, READ can require WRITE and vice-versa
hence this issues.

The BEV_CTRL_GET_FD hunk to fix http subsystem, since it depends from what
bufferevent_getfd() returns.

Fixes: #428
Fixes: ssl/bufferevent_filter_write_after_connect
Fixes: http/https_filter_chunk_out
Fixes: da52933550fd4736aa1c213b6de497e2ffc31e34 ("be_openssl: don't call
do_write() directly from outbuf_cb")