Fix network timeout/error handling in negotiator prefetch code. #6164
Fix network timeout/error handling in negotiator prefetch code. #6164

Handling for timeout or error from select() is no longer dead code.
Send an END_NEGOTIATE and then close the socket to problematic schedds.

htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor