Fix. open:update() method may overflow out buffer.
```
EVP_DecryptUpdate
...
if padding is enabled the decrypted data buffer `out` passed to EVP_DecryptUpdate()
should have sufficient room for (inl + cipher_block_size) bytes
unless the cipher block size is 1 in which case `inl` bytes is sufficient.
```
Add. LCRYPTO_MAX_BUFFER_SIZE macro defines maximum size of temporary buffer used by update methods.
All update methods (encrypt/decrypt/open/seal) use same implementation.