fscrypt: catch up to v4.11-rc1

Keep validate_user_key() due to kasprintf() panic.

fscrypt:
- skcipher_ -> ablkcipher_
- fs/crypto/bio.c changes

f2fs:
- fscrypt: use ENOKEY when file cannot be created w/o key
- fscrypt: split supp and notsupp declarations into their own headers
- fscrypt: make fscrypt_operations.key_prefix a string

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
17 files changed