x86, irq: Move irq_remapping_enabled declaration to iommu code

Remove the last left-over from this flag from x86 code.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index 95363ac..ecb6376 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -34,6 +34,7 @@
 extern int disable_irq_remap;
 extern int disable_sourceid_checking;
 extern int no_x2apic_optout;
+extern int irq_remapping_enabled;
 
 struct irq_remap_ops {
 	/* Check whether Interrupt Remapping is supported */