Chuck Ebbert noticed that the desc_empty macro is incorrect.  Fix it.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Index: linux-2.6.13/include/asm-i386/desc.h
===================================================================
--- linux-2.6.13.orig/include/asm-i386/desc.h	2005-08-15 11:23:32.000000000 -0700
+++ linux-2.6.13/include/asm-i386/desc.h	2005-08-16 10:49:03.000000000 -0700
@@ -18,7 +18,7 @@
 #include <asm/mmu.h>
 
 #define desc_empty(desc) \
-		(!((desc)->a + (desc)->b))
+		(!((desc)->a | (desc)->b))
 
 #define desc_equal(desc1, desc2) \
 		(((desc1)->a == (desc2)->a) && ((desc1)->b == (desc2)->b))