mips: move cache declarations into header

Some of the cache functions are declared only for their callers, e.g.

arch/mips/mm/c-r3k.c:28:15: error: no previous prototype for 'r3k_cache_size' [-Werror=missing-prototypes]
arch/mips/mm/c-r3k.c:63:15: error: no previous prototype for 'r3k_cache_lsize' [-Werror=missing-prototypes]
arch/mips/mm/c-r4k.c:1703:6: error: no previous prototype for 'r4k_cache_init' [-Werror=missing-prototypes]
arch/mips/mm/sc-mips.c:255:5: error: no previous prototype for 'mips_sc_init' [-Werror=missing-prototypes]

Move all the declarations to asm/cache.h and asm/r4kcache.h where they
can be seen by the function definitions.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnd Bergmann <[e-mail]>
Cc: Stephen Rothwell <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

arch/mips/include/asm/cache.h

···
 #define __read_mostly __section(".data..read_mostly")
 
 extern void cache_noop(void);
+extern void r3k_cache_init(void);
+extern unsigned long r3k_cache_size(unsigned long);
+extern unsigned long r3k_cache_lsize(unsigned long);
+extern void r4k_cache_init(void);
+extern void octeon_cache_init(void);
+extern void au1x00_fixup_config_od(void);
 
 #endif /* _ASM_CACHE_H */

arch/mips/include/asm/r4kcache.h

···
 #include <asm/mmzone.h>
 #include <asm/unroll.h>
 
+extern void r5k_sc_init(void);
+extern void rm7k_sc_init(void);
+extern int mips_sc_init(void);
+
 extern void (*r4k_blast_dcache)(void);
 extern void (*r4k_blast_icache)(void);
 

arch/mips/kernel/cpu-probe.c

···
 static inline int cpu_has_confreg(void)
 {
 #ifdef CONFIG_CPU_R3000
-	extern unsigned long r3k_cache_size(unsigned long);
 	unsigned long size1, size2;
 	unsigned long cfg = read_c0_conf();
 

arch/mips/kernel/cpu-r3k-probe.c

···
 static inline int cpu_has_confreg(void)
 {
 #ifdef CONFIG_CPU_R3000
-	extern unsigned long r3k_cache_size(unsigned long);
 	unsigned long size1, size2;
 	unsigned long cfg = read_c0_conf();
 

arch/mips/mm/c-r4k.c

···
 	return;
 }
 
-extern int r5k_sc_init(void);
-extern int rm7k_sc_init(void);
-extern int mips_sc_init(void);
-
 static void setup_scache(void)
 {
 	struct cpuinfo_mips *c = &current_cpu_data;

arch/mips/mm/cache.c

···
 void cpu_cache_init(void)
 {
 	if (cpu_has_3k_cache) {
-		extern void __weak r3k_cache_init(void);
-
 		r3k_cache_init();
 	}
 	if (cpu_has_4k_cache) {
-		extern void __weak r4k_cache_init(void);
-
 		r4k_cache_init();
 	}
 
 	if (cpu_has_octeon_cache) {
-		extern void __weak octeon_cache_init(void);
-
 		octeon_cache_init();
 	}