MIPS: SGI-IP27: collect externs in new header file

IP27 code has a few externs distributed over .c files. Collect them
together into one commcon header file.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

arch/mips/sgi-ip27/ip27-common.h

@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __IP27_COMMON_H
+#define __IP27_COMMON_H
+
+extern void ip27_reboot_setup(void);
+extern void hub_rt_clock_event_init(void);
+
+#endif /* __IP27_COMMON_H */

arch/mips/sgi-ip27/ip27-init.c

@@ -36,6 +36,8 @@
 #include <asm/sn/sn0/ip27.h>
 #include <asm/sn/mapped_kernel.h>
 
+#include "ip27-common.h"
+
 #define CPU_NONE		(cpuid_t)-1
 
 static DECLARE_BITMAP(hub_init_mask, MAX_COMPACT_NODES);
@@ -113,8 +115,6 @@ get_nasid(void)
 			 >> NSRI_NODEID_SHFT);
 }
 
-extern void ip27_reboot_setup(void);
-
 void __init plat_mem_setup(void)
 {
 	u64 p, e, n_mode;

arch/mips/sgi-ip27/ip27-reset.c

@@ -26,6 +26,8 @@
 #include <asm/sn/gda.h>
 #include <asm/sn/sn0/hub.h>
 
+#include "ip27-common.h"
+
 void machine_restart(char *command) __noreturn;
 void machine_halt(void) __noreturn;
 void machine_power_off(void) __noreturn;

arch/mips/sgi-ip27/ip27-smp.c

@@ -27,6 +27,8 @@
 #include <asm/sn/sn0/hubio.h>
 #include <asm/sn/sn0/ip27.h>
 
+#include "ip27-common.h"
+
 /*
  * Takes as first input the PROM assigned cpu id, and the kernel
  * assigned cpu id as the second.
@@ -147,8 +149,6 @@ static void ip27_init_cpu(void)
 
 static void ip27_smp_finish(void)
 {
-	extern void hub_rt_clock_event_init(void);
-
 	hub_rt_clock_event_init();
 	local_irq_enable();
 }

arch/mips/sgi-ip27/ip27-timer.c

@@ -38,6 +38,8 @@
 #include <asm/sn/sn0/hubio.h>
 #include <asm/pci/bridge.h>
 
+#include "ip27-common.h"
+
 static int rt_next_event(unsigned long delta, struct clock_event_device *evt)
 {
 	unsigned int cpu = smp_processor_id();