Blackfin: SMP: fix hotplug building after irq header shuffle

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/mach-bf561/hotplug.c

@@ -6,7 +6,9 @@
  */
 
 #include <asm/blackfin.h>
+#include <asm/irq.h>
 #include <asm/smp.h>
+
 #define SIC_SYSIRQ(irq)	(irq - (IRQ_CORETMR + 1))
 
 int hotplug_coreb;