eis: don't log a warning for a disconnecting client that's disconnected
Two commits, one reshuffling the log order so it makes it easier to spot when exactly a connection error occurred.
The second one fixes this mutter input test case failure.
Those tests trap on libei errors and we're guaranteed to get a log error when the tests call ei_unref(), closing the fd and causing a Connection error in libeis - even though the client wanted to be disconnected anyway.