[PATCH] remove redundant NULL checks before kfree() in sound/ and avoid casting pointers about to be kfree()'ed

Checking a pointer for NULL before calling kfree() on it is redundant,
kfree() deals with NULL pointers just fine.
This patch removes such checks from sound/

This patch also makes another, but closely related, change.
It avoids casting pointers about to be kfree()'ed.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

sound/oss/maestro.c

@@ -2356,7 +2356,7 @@ ess_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 	}
 
 rec_return_free:
-	if(combbuf) kfree(combbuf);
+	kfree(combbuf);
 	return ret;
 }