cr50: switch ECDSA to use enum dcrypto_result, added FIPS checks

We have to block access to crypto functions when FIPS errors occurred.
To achieve this:
1. Provide wrappers for ECDSA P-256 sign and verify functions
   a) DCRYPTO_p256_ecdsa_verify as wrapper for dcrypto_p256_ecdsa_verify
   b) DCRYPTO_p256_ecdsa_sign as wrapper for
      dcrypto_p256_fips_sign_internal with additional check for FIPS
      DRBG initialization which is needed for signing.
2. Switch all ECDSA functions, both internal and external to use
   enum dcrypto_result instead of inconsistent 0/1 values.
3. Added warning for unused result code for ECDSA functions.
4. Updated documentation for public APIs
5. In DCRYPTO_p256_key_from_bytes() implemented clear distinction between
   bad candidate and failures due to FIPS or pair-wise consistency.
6. U2F, rma_auth, TPM ecc, etc updated to use new return codes.

BUG=b:197893750
TEST=make BOARD=cr50 CRYPTO_TEST=1; rma_auth, u2f_test, etc.
test/tpm_test/tpmtest.py
TCG tests
----------------------------- Test Result Summary ----------------------
  Test executed on:		Thu Sep 23 09:56:42 2021
  Performed Tests:		248
  Passed Tests:			248
  Failed Tests:			0
  Errors:			0
  Warnings:			0
========================================================================

Signed-off-by: Vadim Sukhomlinov <sukhomlinov@google.com>
Change-Id: I0251bf511771c1c1fd281f6db706d1dedac3e8b8
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3179708
Reviewed-by: Vadim Sukhomlinov <sukhomlinov@chromium.org>
Reviewed-by: Andrey Pronin <apronin@chromium.org>
Commit-Queue: Vadim Sukhomlinov <sukhomlinov@chromium.org>
Tested-by: Vadim Sukhomlinov <sukhomlinov@chromium.org>
Auto-Submit: Vadim Sukhomlinov <sukhomlinov@chromium.org>

0 files changed, 0 insertions, 0 deletions