migration: Wait for blocking IO

We have three conditions here:
- channel fails -> error
- we have to quit: we close the channel and reads fails
- normal read that success, we are in bussiness

So forget the complications of waiting in a semaphore.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
1 file changed