on cygwin, epicsSocketEnablePortUseForDatagramFanout: unable to set SO_REUSEADDR?

This is cygwin feature - a situation where cygwin doesnt behave like posix. On posix we have the attached. To fix this someone will need to add an implementation of epicsSocketEnableAddressUseForDatagramFanout for cygwin that behaves like win32, or just use the native port its much more efficient.

/*
 * SO_REUSEPORT is not in POSIX
 */
epicsShareFunc void epicsShareAPI
    epicsSocketEnableAddressUseForDatagramFanout ( SOCKET s )
{
    int yes = true;
    int status;
    status = setsockopt ( s, SOL_SOCKET, SO_REUSEADDR,
        (char *) & yes, sizeof ( yes ) );
    if ( status < 0 ) {
        errlogPrintf (
            "epicsSocketEnablePortUseForDatagramFanout: "
            "unable to set SO_REUSEADDR\n");
    }
}

Original Mantis Bug: mantis-304
    http://www.aps.anl.gov/epics/mantis/view_bug_page.php?f_id=304