f2fs: mark f2fs_init_compress_mempool w/ __init

f2fs_init_compress_mempool() only initializes the memory pool during
the f2fs module init phase. Let's mark it as __init like any other
function.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/compress.c

@@ -564,7 +564,7 @@ module_param(num_compress_pages, uint, 0444);
 MODULE_PARM_DESC(num_compress_pages,
 		"Number of intermediate compress pages to preallocate");
 
-int f2fs_init_compress_mempool(void)
+int __init f2fs_init_compress_mempool(void)
 {
 	compress_page_pool = mempool_create_page_pool(num_compress_pages, 0);
 	return compress_page_pool ? 0 : -ENOMEM;

fs/f2fs/f2fs.h

@@ -4251,7 +4251,7 @@ bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
 int f2fs_truncate_partial_cluster(struct inode *inode, u64 from, bool lock);
 void f2fs_compress_write_end_io(struct bio *bio, struct page *page);
 bool f2fs_is_compress_backend_ready(struct inode *inode);
-int f2fs_init_compress_mempool(void);
+int __init f2fs_init_compress_mempool(void);
 void f2fs_destroy_compress_mempool(void);
 void f2fs_decompress_cluster(struct decompress_io_ctx *dic, bool in_task);
 void f2fs_end_read_compressed_page(struct page *page, bool failed,
@@ -4320,7 +4320,7 @@ static inline struct page *f2fs_compress_control_page(struct page *page)
 	WARN_ON_ONCE(1);
 	return ERR_PTR(-EINVAL);
 }
-static inline int f2fs_init_compress_mempool(void) { return 0; }
+static inline int __init f2fs_init_compress_mempool(void) { return 0; }
 static inline void f2fs_destroy_compress_mempool(void) { }
 static inline void f2fs_decompress_cluster(struct decompress_io_ctx *dic,
 				bool in_task) { }