queryport: Remove read timeout for client conn

The server's receive loop shouldn't timeout if no
clients are writing to the connection (idle conn).

Change-Id: I92f37b326e4771eff0fbbdaf713e0cd6066b873b
Reviewed-on: http://review.couchbase.org/43481
Reviewed-by: Sarath Lakshman <sarath@couchbase.com>
Tested-by: Sarath Lakshman <sarath@couchbase.com>