mc_tmpdir(), system recovery and read-only /tmp

[Pavel Roskin]

> Recent patch makes mc unusable for system recovery when / is mounted 
> read-only, and there is no /tmp/mc-root.  Also it does not check 
> ownership and modes if such directory existed, and so it can be used for 
>   some kinds of DOS in mc.

Indeed, that should be fixed.  I have added this to src/TODO and marked it 
as a regression.

-- 
Regards,
Pavel Roskin