ecryptfs: Remove unused declartion ecryptfs_fill_zeros()

The definition of ecryptfs_fill_zeros() has been removed since
commit b6c1d8f ("eCryptfs: remove unused functions and kmem_cache")
So, Remove the empty declartion in header files.

Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>

Author: Zhang Zekun

fs/ecryptfs/ecryptfs_kernel.h

@@ -542,7 +542,6 @@ int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
 					 size_t *decrypted_name_size,
 					 struct super_block *sb,
 					 const char *name, size_t name_size);
-int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
 int ecryptfs_encrypt_and_encode_filename(
 	char **encoded_name,
 	size_t *encoded_name_size,