[PATCH RFC 2/5] apic: use symbolic APIC_EOI_ACK

["Michael S. Tsirkin" <mst@redhat.com>]

Use the symbol instead of hard-coded numbers,
now that the reason for the value is documented
where the constant is defined we don't need to
duplicate this explanation in code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 arch/x86/include/asm/apic.h |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index d854101..a09e9ab 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -463,9 +463,7 @@ static inline void ack_APIC_irq(void)
 	 * ack_APIC_irq() actually gets compiled as a single instruction
 	 * ... yummie.
 	 */
-
-	/* Docs say use 0 for future compatibility */
-	apic_write(APIC_EOI, 0);
+	apic_write(APIC_EOI, APIC_EOI_ACK);
 }
 
 static inline unsigned default_get_apic_id(unsigned long x)
-- 
1.7.9.111.gf3fb0