[Vortex] PATCH: Fix crash when channel-open is refused

[Francis Brosnan Blazquez]

Hi Jens,

> Just hit a reproducible crash opening a channel, when the remote
> peer  
> refuses. It's in __vortex_channel_new, and it looks like there's a  
> missing test for NULL on the 'channel' variable, at line 3342:
>                 if (channel->is_opened &&
> vortex_channel_have_piggyback (channel)) {
> The lines just before do test for NULL, but this line crashes.

Good. I've updated regression test to reproduce and check the patch you
have provided. It is now applied with some minor indent modifications
and ported into 1.1 series. I've taken advantage to also introduce some
checks for error codes returned on channel failure creation. 

Thanks for reporting Jens. Cheers!
-- 
Francis Brosnan Blazquez <francis at aspl.es>
Advanced Software Production Line, S.L.