ARM: davinci: fix davinci_cpufreq_init() declaration

The davinci_cpufreq_init() declaration is only seen by its caller
but not the definition:

drivers/cpufreq/davinci-cpufreq.c:153:12: error: no previous prototype for 'davinci_cpufreq_init'

Move it into the platform_data header that is already used an
interface between the two places.

Acked-by: Bartosz Golaszewski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnd Bergmann <[e-mail]>

arch/arm/mach-davinci/common.c

···
 #include <linux/etherdevice.h>
 #include <linux/davinci_emac.h>
 #include <linux/dma-mapping.h>
+#include <linux/platform_data/davinci-cpufreq.h>
 
 #include <asm/tlb.h>
 #include <asm/mach/map.h>

arch/arm/mach-davinci/common.h

···
 extern void davinci_init_ide(void);
 void davinci_init_late(void);
 
-#ifdef CONFIG_CPU_FREQ
-int davinci_cpufreq_init(void);
-#else
-static inline int davinci_cpufreq_init(void) { return 0; }
-#endif
-
 #ifdef CONFIG_SUSPEND
 int davinci_pm_init(void);
 #else

include/linux/platform_data/davinci-cpufreq.h

···
 	int (*init)(void);
 };
 
+#ifdef CONFIG_CPU_FREQ
+int davinci_cpufreq_init(void);
+#else
+static inline int davinci_cpufreq_init(void) { return 0; }
+#endif
+
 #endif /* _MACH_DAVINCI_CPUFREQ_H */