irq_remapping: Use apic_ack_irq()

To address the EBUSY fail of interrupt affinity settings in case that the
previous setting has not been cleaned up yet, use the new apic_ack_irq()
function instead of the special ir_ack_apic_edge() implementation which is
merily a wrapper around ack_APIC_irq().

Preparatory change for the real fix

Fixes: dccfe3147b ("x86/vector: Simplify vector move cleanup")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Song Liu <songliubraving@fb.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <liu.song.a23@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: stable@vger.kernel.org
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tariq Toukan <tariqt@mellanox.com>
Link: https://lkml.kernel.org/r/20180604162224.555716895@linutronix.de

drivers/iommu/amd_iommu.c

@@ -4379,7 +4379,7 @@ static void ir_compose_msi_msg(struct irq_data *irq_data, struct msi_msg *msg)
 
 static struct irq_chip amd_ir_chip = {
 	.name			= "AMD-IR",
-	.irq_ack		= ir_ack_apic_edge,
+	.irq_ack		= apic_ack_irq,
 	.irq_set_affinity	= amd_ir_set_affinity,
 	.irq_set_vcpu_affinity	= amd_ir_set_vcpu_affinity,
 	.irq_compose_msi_msg	= ir_compose_msi_msg,