crypto: sha256 - Use same state format as legacy drivers

Make the export and import functions for the sha224, sha256,
hmac(sha224), and hmac(sha256) shash algorithms use the same format as
the padlock-sha and nx-sha256 drivers, as required by Herbert.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250630160645.3198-11-ebiggers@kernel.org


Signed-off-by: Eric Biggers <ebiggers@kernel.org>