[PATCH] bfd: add missing smclass when creating csect for xcoff64

[CHIGOT, CLEMENT]

Hi Alan, 

> > This one is pretty simple, so I know that it won't change anyway. 
> 
> Maybe too simple.  You've added new sections without handling them at
> all in aix.sc, and in the case of .tl and .ul I'm fairly sure you will
> need to add quite a lot of code for thread-local support.  It is fine
> to have small patches in a series, but this patch in isolation is
> obviously incomplete.
> 
> So I'd like to see a little more before committing the patch.

Yes indeed, I've 6 patches coming up aiming to enable both TLS and large TOC
(not -bbigtoc from AIX ld, but the TOC generated when -mcmodel=large is passed
to gcc, making use of R_TOCU and R_TOCL relocations). 

I'll send them as a series. 

Clément