Remove exception when using SO_REUSEADDR on Linux (#3856)

Remove exception when using SO_REUSEADDR on Linux (#3856)

SO_REUSEADDR and SO_REUSEPORT are fundamentally different. This
exception seems to have been put in place to address the lack of
the latter on older Linux kernels for TCP. However, the change in
fact raises an exception when SO_REUSEADDR is used, which causes
failures in server applications, which may use SO_REUSEADDR to
avoid WAIT state timeouts.

Description of SO_REUSEADDR and SO_REUSEPORT differences:

http://stackoverflow.com/questions/14388706/socket-options-so-reuseaddr-and-so-reuseport-how-do-they-differ-do-they-mean-t

Some problems caused by raising this exception:

https://github.com/zeromq/netmq/issues/623
https://github.com/zeromq/netmq/issues/592
https://github.com/fsprojects/IfSharp/issues/90