bpo-37630: Use SHA3 and SHAKE XOF from OpenSSL (GH-16049)



OpenSSL 1.1.1 comes with SHA3 and SHAKE builtin.

Signed-off-by: Christian Heimes <christian@python.org>

Automerge-Triggered-By: @tiran
diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
index b737d22..d644974 100644
--- a/Doc/library/hashlib.rst
+++ b/Doc/library/hashlib.rst
@@ -87,6 +87,8 @@
    that the hashing algorithm is not used in a security context, e.g. as a
    non-cryptographic one-way compression function.
 
+   Hashlib now uses SHA3 and SHAKE from OpenSSL 1.1.1 and newer.
+
 For example, to obtain the digest of the byte string ``b'Nobody inspects the
 spammish repetition'``::