aes: The API now has 3 seperate functions for 128/192/256 key size

The main aes_key_init() became static and user can call it only via
aes128_key_init()/aes192_key_init()/aes256_key_init(). So there is no
point to return int.
sha2: sha2 API now has 2 seperate functions for sha224/256.

The main sha2() became static and user can call it only via sha224() or
sha256() so there is no point to return int.