ppc64: Add declarations to ppc64 headers as well as powerpc headers

For now, we need these declarations that we moved from C code in
the asm-ppc64 versions of these headers as well as the asm-powerpc
versions.  The asm-ppc64 versions will be disappearing shortly.
Signed-off-by: Paul Mackerras <paulus@samba.org>

include/asm-ppc64/prom.h

@@ -204,6 +204,8 @@ extern void of_detach_node(const struct device_node *);
 extern unsigned long prom_init(unsigned long, unsigned long, unsigned long,
 	unsigned long, unsigned long);
 extern void finish_device_tree(void);
+extern void unflatten_device_tree(void);
+extern void early_init_devtree(void *);
 extern int device_is_compatible(struct device_node *device, const char *);
 extern int machine_is_compatible(const char *compat);
 extern unsigned char *get_property(struct device_node *node, const char *name,

include/asm-ppc64/system.h

@@ -149,6 +149,8 @@ struct thread_struct;
 extern struct task_struct * _switch(struct thread_struct *prev,
 				    struct thread_struct *next);
 
+extern unsigned long klimit;
+
 extern int powersave_nap;	/* set if nap mode can be used in idle loop */
 
 /*