crypto: arm64/sha - fix function types

Instead of casting pointers to callback functions, add C wrappers
to avoid type mismatch failures with Control-Flow Integrity (CFI)
checking.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>