Add RNG params to private key parsing

This is necessary for the case where the public part of an EC keypair
needs to be computed from the private part - either because it was not
included (it's an optional component) or because it was compressed (a
format we can't parse).

This changes the API of two public functions: mbedtls_pk_parse_key() and
mbedtls_pk_parse_keyfile().

Tests and programs have been adapted. Some programs use a non-secure RNG
(from the test library) just to get things to compile and run; in a
future commit this should be improved in order to demonstrate best
practice.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/library/psa_crypto_rsa.c b/library/psa_crypto_rsa.c
index f2e9a1c..ef2adc1 100644
--- a/library/psa_crypto_rsa.c
+++ b/library/psa_crypto_rsa.c
@@ -108,7 +108,8 @@
     /* Parse the data. */
     if( PSA_KEY_TYPE_IS_KEY_PAIR( type ) )
         status = mbedtls_to_psa_error(
-            mbedtls_pk_parse_key( &ctx, data, data_length, NULL, 0 ) );
+            mbedtls_pk_parse_key( &ctx, data, data_length, NULL, 0,
+                mbedtls_psa_get_random, MBEDTLS_PSA_RANDOM_STATE ) );
     else
         status = mbedtls_to_psa_error(
             mbedtls_pk_parse_public_key( &ctx, data, data_length ) );