Hashlib on SAMD

[brentru]

Hashlib is not supported on SAMD ports of CircuitPython.

The SHA256 is useful for a RSA implementation I'm working on. SHA1 is useful for TOTP, and MD5 may come in handy for performing checksums for files on CIRCUITPY.

[tannewt]

Note the SAMD51 has a Public Key Cryptography Controller (PUKCC) that is meant to help with these algorithms.

[ladyada]

yes! and other chips don't, having generic C is fine and for large chips only

[applecuckoo]

Related: #4504

The Integrity Check Monitor (ICM) built into the SAMD51 doesn't support MD5 and neither do the chips I mention in that latest post.