pitr: fix deadlock in ff code
pitr: fix deadlock in ff code

During fast-forward, the VStream code can get stuck sending
data to the channel. This will cause Close to hang waiting
for VStream to exit. I've changed the VStream call back to
end the stream as soon as the target position was reached.

Signed-off-by: Sugu Sougoumarane <b9023a093a3fde2f5ed7cdf696263add90aef9db@gmail.com>

vitessio/vitess,tinyspeck/vitess,mahak/vitess,vitessio/vitess,mahak/vitess,tinyspeck/vitess,mahak/vitess,mahak/vitess,tinyspeck/vitess,mahak/vitess,vitessio/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,vitessio/vitess,mahak/vitess,vitessio/vitess,vitessio/vitess,tinyspeck/vitess,tinyspeck/vitess