x86-32: Fix atomic64_add_unless return value convention

atomic64_add_unless must return 1 if it perfomed the add and 0 otherwise.
The implementation did the opposite thing.

Reported-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
LKML-Reference: <1267469749-11878-3-git-send-email-luca@luca-barbieri.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/lib/atomic64_386_32.S

@@ -133,13 +133,13 @@ BEGIN add_unless %ecx
 1:
 	movl %eax,  ($v)
 	movl %edx, 4($v)
-	xorl %eax, %eax
+	movl $1, %eax
 2:
 RETURN
 3:
 	cmpl %edx, %edi
 	jne 1b
-	movl $1, %eax
+	xorl %eax, %eax
 	jmp 2b
 END_
 

arch/x86/lib/atomic64_cx8_32.S

@@ -180,7 +180,7 @@ ENTRY(atomic64_add_unless_cx8)
 	cmpxchg8b (%ebp)
 	jne 1b
 
-	xorl %eax, %eax
+	movl $1, %eax
 3:
 	addl $8, %esp
 	CFI_ADJUST_CFA_OFFSET -8
@@ -190,7 +190,7 @@ ENTRY(atomic64_add_unless_cx8)
 4:
 	cmpl %edx, 4(%esp)
 	jne 2b
-	movl $1, %eax
+	xorl %eax, %eax
 	jmp 3b
 	CFI_ENDPROC
 ENDPROC(atomic64_add_unless_cx8)