sparc64: fix sparse warning in kgdb_64.c

Fix following warnings:
kgdb_64.c:114:18: warning: symbol 'smp_kgdb_capture_client' was not declared. Should it be static?
kgdb_64.c:161:17: warning: symbol 'kgdb_trap' was not declared. Should it be static?

Add proper prototypes

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/kernel.h b/arch/sparc/kernel/kernel.h
index 8021372..e7f652b 100644
--- a/arch/sparc/kernel/kernel.h
+++ b/arch/sparc/kernel/kernel.h
@@ -41,6 +41,9 @@
 void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs);
 void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs);
 
+/* kgdb_64.c */
+void __irq_entry smp_kgdb_capture_client(int irq, struct pt_regs *regs);
+
 /* pci.c */
 int pci64_dma_supported(struct pci_dev *pdev, u64 device_mask);