[PATCH -next] arm64: smp: Add missing prototype for some smp.c functions

[Chen Lifu]

In commit eb631bb5bf5b
("arm64: Support arch_irq_work_raise() via self IPIs") a new
function "arch_irq_work_raise" was added without a prototype
in header irq_work.h

In commit d914d4d49745
("arm64: Implement panic_smp_self_stop()") a new
function "panic_smp_self_stop" was added without a prototype
in header irq_work.h

We get the following warnings on W=1:
arch/arm64/kernel/smp.c:842:6: warning: no previous prototype
for ‘arch_irq_work_raise’ [-Wmissing-prototypes]
arch/arm64/kernel/smp.c:862:6: warning: no previous prototype
for ‘panic_smp_self_stop’ [-Wmissing-prototypes]

Fix the same by adding the missing prototype in header irq_work.h

Signed-off-by: Chen Lifu <chenlifu at huawei.com>
---
 arch/arm64/include/asm/irq_work.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/include/asm/irq_work.h b/arch/arm64/include/asm/irq_work.h
index a1020285ea75..f766e2190e7c 100644
--- a/arch/arm64/include/asm/irq_work.h
+++ b/arch/arm64/include/asm/irq_work.h
@@ -2,6 +2,9 @@
 #ifndef __ASM_IRQ_WORK_H
 #define __ASM_IRQ_WORK_H
 
+extern void arch_irq_work_raise(void);
+extern void panic_smp_self_stop(void);
+
 static inline bool arch_irq_work_has_interrupt(void)
 {
 	return true;
-- 
2.17.1