nilfs2: remove obsolete declarations of cache constructor and destructor

The commit 41c88bd7 ("nilfs2: cleanup multi
kmem_cache_{create,destroy} code") consolidated slab constructors and
destructors used in nilfs, but it left some declarations in header
files.

This gets rid of the obsolete declarations.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

fs/nilfs2/btree.h

@@ -75,8 +75,6 @@ struct nilfs_btree_path {
 
 extern struct kmem_cache *nilfs_btree_path_cache;
 
-int nilfs_btree_path_cache_init(void);
-void nilfs_btree_path_cache_destroy(void);
 int nilfs_btree_init(struct nilfs_bmap *);
 int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
 				   const __u64 *, const __u64 *, int);

fs/nilfs2/segbuf.h

@@ -127,8 +127,6 @@ struct nilfs_segment_buffer {
 
 extern struct kmem_cache *nilfs_segbuf_cachep;
 
-int __init nilfs_init_segbuf_cache(void);
-void nilfs_destroy_segbuf_cache(void);
 struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *);
 void nilfs_segbuf_free(struct nilfs_segment_buffer *);
 void nilfs_segbuf_map(struct nilfs_segment_buffer *, __u64, unsigned long,

fs/nilfs2/segment.h

@@ -221,8 +221,6 @@ enum {
 extern struct kmem_cache *nilfs_transaction_cachep;
 
 /* segment.c */
-extern int nilfs_init_transaction_cache(void);
-extern void nilfs_destroy_transaction_cache(void);
 extern void nilfs_relax_pressure_in_lock(struct super_block *);
 
 extern int nilfs_construct_segment(struct super_block *);