common code patch for Solaris

[Artem Kachitchkine]

> Btw, do you have plans to add the Solaris back-end to the git master
> repo and if yes when do you expect this to happen?

Absolutely. It should happen within the next 4 weeks.

As a matter of heads-up, we'll also have a large patch that won't make the 
upstream yet - it will be available as part of the OpenSolaris code. The patch 
is to support thin client environments such as Sun Ray: it adds per-user GDLs, 
which are populated either automatically at session login time, when volume 
manager starts and "claims" a HAL tree branch; claiming a branch makes it 
invisible to other users. It's a Solaris-specific patch primarily due to 
schedule pressure. Eventually we should come to some sort of general solution 
that works on all HAL OSes.

-Artem.