Use attribute accessor functions in driver wrappers

Fully automated:
```
perl -i -pe 's/(\w+)->core\.(\w+)/psa_get_key_$2($1)/g' scripts/data_files/driver_templates/*.jinja docs/psa-driver-example-and-guide.md
```

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/docs/psa-driver-example-and-guide.md b/docs/psa-driver-example-and-guide.md
index d041723..aa825ad 100644
--- a/docs/psa-driver-example-and-guide.md
+++ b/docs/psa-driver-example-and-guide.md
@@ -157,11 +157,11 @@
 
 ```
 #if defined (MBEDTLS_PSA_P256M_DRIVER_ENABLED)
-            if( PSA_KEY_TYPE_IS_ECC( attributes->core.type ) &&
+            if( PSA_KEY_TYPE_IS_ECC( psa_get_key_type(attributes) ) &&
                 PSA_ALG_IS_ECDSA(alg) &&
                 !PSA_ALG_ECDSA_IS_DETERMINISTIC( alg ) &&
-                PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->core.type) == PSA_ECC_FAMILY_SECP_R1 &&
-                attributes->core.bits == 256 )
+                PSA_KEY_TYPE_ECC_GET_FAMILY(psa_get_key_type(attributes)) == PSA_ECC_FAMILY_SECP_R1 &&
+                psa_get_key_bits(attributes) == 256 )
             {
                 status = p256_transparent_sign_hash( attributes,
                                                      key_buffer,