Use remove_key_data_from_memory instead of wipe_key_slot

Since the loading attempt of a builtin key might be followed by trying
to load a persistent key, we can only wipe the allocated key data, not
the associated metadata.

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>

library/psa_crypto.c

@@ -1063,8 +1063,7 @@ static psa_status_t psa_get_and_lock_transparent_key_slot_with_policy(
     psa_get_and_lock_key_slot_with_policy( key, p_slot, usage, alg )
 #endif /* MBEDTLS_PSA_CRYPTO_SE_C */
 
-/** Wipe key data from a slot. Preserve metadata such as the policy. */
-static psa_status_t psa_remove_key_data_from_memory( psa_key_slot_t *slot )
+psa_status_t psa_remove_key_data_from_memory( psa_key_slot_t *slot )
 {
     /* Data pointer will always be either a valid pointer or NULL in an
      * initialized slot, so we can just free it. */

library/psa_crypto_core.h

@@ -195,6 +195,9 @@ psa_status_t psa_wipe_key_slot( psa_key_slot_t *slot );
 psa_status_t psa_allocate_buffer_to_slot( psa_key_slot_t *slot,
                                           size_t buffer_length );
 
+/** Wipe key data from a slot. Preserves metadata such as the policy. */
+psa_status_t psa_remove_key_data_from_memory( psa_key_slot_t *slot );
+
 /** Copy key data (in export format) into an empty key slot.
  *
  * This function assumes that the slot does not contain

library/psa_crypto_slot_management.c

@@ -327,7 +327,7 @@ static psa_status_t psa_load_builtin_key_into_slot( psa_key_slot_t *slot )
 
 exit:
     if( status != PSA_SUCCESS )
-        psa_wipe_key_slot( slot );
+        psa_remove_key_data_from_memory( slot );
     return( status );
 }
 #endif /* MBEDTLS_PSA_CRYPTO_BUILTIN_KEYS */