Remove support for blocking connect()

Remove support for blocking connect()

It is hard to imagine that we still have any supported OS that does
not support non-blocking connect while still supporting non-blocking
sockets in general.

Patch V2: remove epoll.h removal that should have been in other patch.
Patch V3: remove another instance in socket.c that I misseds in v1

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20210503105850.3903732-1-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg22291.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>