crypto/internal/fips140test: make TestCASTFailures standalone
We want it to work even when fips140test.test is cross-compiled and
moved to a different machine. Also, make it log more.
Change-Id: I6a6a46566712f05f6b551ecde75672baf2c0fc6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/644644 Reviewed-by: Ian Lance Taylor <iant@google.com> Reviewed-by: Roland Shoemaker <roland@golang.org> Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Filippo Valsorda <filippo@golang.org>