crypto/internal/fips/sha3: import x/crypto/sha3@750a45fe5e4

crypto/internal/fips/sha3: import x/crypto/sha3@750a45fe5e4

For now just internally, pending a dedicated proposal for the exposed
package API.

In this CL the code is copied verbatim, for ease of review. Only the
imports were replaced with the corresponding internal ones, and
crypto.RegisterHash calls were disabled. Also, the 0.5MB keccakkats file
was dropped, supplanted by TestCSHAKEAccumulated and ACVP tests.

Updates #65269
Updates #69982
For #69536

Change-Id: Ia4735b50c99b9573a5c4889733c4a119930fe658
Reviewed-on: https://go-review.googlesource.com/c/go/+/616717
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>