How can I make aead transformations on the new API allocate some context 
space inside
the aead_request?
Description/comments of aead_alg->init() and crypto_alg->cra_init() 
suggest that they are
triggered after the tfm object has already been allocated, so setting 
crypto_aead->reqsize
has no effect.
Also, it seems that if aead_alg->init() is triggered, but 
crypto_alg->cra_init() is not.
I see a call to alg->cra_init() from crypto_create_tfm, when allocating 
an aead transformation,
but my cra_init() is not actually called. Instead aead_alg->init() is 
not seen anywhere, but
indeed it is triggered at some time. Where does it get called?