ssl_tls12_populate_transform using PSA_ALG_AEAD

- ssl_tls12_populate_transform using PSA_ALG_AEAD_WITH_SHORTENED_TAG()
  instead of calling mbedtls_ssl_cipher_to_psa()

Signed-off-by: Glenn Strauss <gstrauss@gluelogic.com>

library/ssl_tls.c

@@ -7492,12 +7492,15 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
 
     if( ssl_mode == MBEDTLS_SSL_MODE_AEAD )
     {
-        transform->taglen =
-            ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
+        transform->taglen = 16;
+        if ( ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG )
+        {
+            transform->taglen = 8;
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-        mbedtls_ssl_cipher_to_psa( ciphersuite_info->cipher, transform->taglen,
-                                   &alg, &key_type, &key_bits );
+            if( alg == PSA_ALG_CCM )
+                alg = PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_CCM, 8 );
 #endif /* MBEDTLS_USE_PSA_CRYPTO */
+        }
     }
 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC_ETM)
     else