Remove unused variable from powerpc sem_post.c

[David Miller]

From: "Joseph S. Myers" <joseph@codesourcery.com>
Date: Tue, 4 Dec 2012 21:24:53 +0000

> Similar to an issue I recently fixed in the generic Linux version of
> this file, the powerpc __old_sem_post has a variable used only to
> store the result of atomic_increment_val, resulting in a warning.
> This patch fixes this warning (tested powerpc32) in the same way as
> the fix to the generic file, by casting the result of
> atomic_increment_val to (void) instead of initializing an unused
> variable with it.
> 
> 2012-12-04  Joseph Myers  <joseph@codesourcery.com>
> 
> 	* sysdeps/unix/sysv/linux/powerpc/sem_post.c (__old_sem_post):
> 	Cast result of atomic_increment_val to (void) instead of storing
> 	in otherwise-unused variable.

I thought we had atomics that didn't return a value and therefore could
be used in situations like this, but I guess not.

Looks fine to me.