x86, intr-remap: fix ack for interrupt remapping

Shouldn't call ack_apic_edge() in ir_ack_apic_edge(), because
ack_apic_edge() does more than just ack: it also does irq migration
in the non-interrupt-remapping case. But there is no such need for
interrupt-remapping case, as irq migration is done in the process
context.

Similarly, ir_ack_apic_level() shouldn't call ack_apic_level, and
instead should do the local cpu's EOI + directed EOI to the io-apic.

ack_x2APIC_irq() is not neccessary, because ack_APIC_irq() will use MSR
write for x2apic, and uncached write for non-x2apic.

[ Impact: simplify/standardize intr-remap IRQ acking, fix on !x2apic ]

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: allen.m.kay@intel.com
Cc: fenghua.yu@intel.com
LKML-Reference: <1239957736-6161-3-git-send-email-weidong.han@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/apic.h

@@ -204,14 +204,6 @@ static inline int x2apic_enabled(void)
 
 extern int get_physical_broadcast(void);
 
-#ifdef CONFIG_X86_X2APIC
-static inline void ack_x2APIC_irq(void)
-{
-	/* Docs say use 0 for future compatibility */
-	native_apic_msr_write(APIC_EOI, 0);
-}
-#endif
-
 extern void apic_disable(void);
 extern int lapic_get_maxlvt(void);
 extern void clear_local_APIC(void);