irqchip/mmp: Declare init functions in common header file

The functions icu_init_irq and mmp2_init_icu are exported
from this code, so declare them in the header file to avoid
the following sparse warnings:

drivers/irqchip/irq-mmp.c:248:13: warning: symbol 'icu_init_irq' was not declared. Should it be static?
drivers/irqchip/irq-mmp.c:271:13: warning: symbol 'mmp2_init_icu' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
[maz: fixup commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220724222152.551850-1-ben-linux@fluff.org

arch/arm/mach-mmp/mmp2.h

@@ -5,13 +5,13 @@
 #include <linux/platform_data/pxa_sdhci.h>
 
 extern void mmp2_timer_init(void);
-extern void __init mmp2_init_icu(void);
 extern void __init mmp2_init_irq(void);
 extern void mmp2_clear_pmic_int(void);
 
 #include <linux/i2c.h>
 #include <linux/platform_data/i2c-pxa.h>
 #include <linux/platform_data/dma-mmp_tdma.h>
+#include <linux/irqchip/mmp.h>
 
 #include "devices.h"
 

arch/arm/mach-mmp/pxa168.h

@@ -5,7 +5,6 @@
 #include <linux/reboot.h>
 
 extern void pxa168_timer_init(void);
-extern void __init icu_init_irq(void);
 extern void __init pxa168_init_irq(void);
 extern void pxa168_restart(enum reboot_mode, const char *);
 extern void pxa168_clear_keypad_wakeup(void);
@@ -18,6 +17,7 @@ extern void pxa168_clear_keypad_wakeup(void);
 #include <linux/pxa168_eth.h>
 #include <linux/platform_data/mv_usb.h>
 #include <linux/soc/mmp/cputype.h>
+#include <linux/irqchip/mmp.h>
 
 #include "devices.h"
 

arch/arm/mach-mmp/pxa910.h

@@ -3,13 +3,13 @@
 #define __ASM_MACH_PXA910_H
 
 extern void pxa910_timer_init(void);
-extern void __init icu_init_irq(void);
 extern void __init pxa910_init_irq(void);
 
 #include <linux/i2c.h>
 #include <linux/platform_data/i2c-pxa.h>
 #include <linux/platform_data/mtd-nand-pxa3xx.h>
 #include <video/mmp_disp.h>
+#include <linux/irqchip/mmp.h>
 
 #include "devices.h"
 

include/linux/irqchip/mmp.h

@@ -4,4 +4,7 @@
 
 extern struct irq_chip icu_irq_chip;
 
+extern void icu_init_irq(void);
+extern void mmp2_init_icu(void);
+
 #endif	/* __IRQCHIP_MMP_H */