multiple xts_encrypt() cannot be performed because the
tweak is not updated. That means that
xts_encrypt(buffer1, tweak)
xts_encrypt(buffer2, tweak)
is not the same as
xts_encrypt(concat(buffer1, buffer2), tweak)
Current patch enables such functionalities by
updating the tweak as output of the encryption.
Note that the tweak is no more constant.
The very same modification is performed
on xts_decrypt()
Signed-off-by: Pascal Brand <pascal.brand@st.com>
