Add missing PSA_KEY_ID_NULL macro.
#define PSA_KEY_LOCATION_VENDOR_FLAG ((psa_key_location_t)0x800000)
+/** The null key identifier.
+ */
+#define PSA_KEY_ID_NULL ((psa_key_id_t)0)
/** The minimum value for a key identifier chosen by the application.
*/
#define PSA_KEY_ID_USER_MIN ((psa_key_id_t)0x00000001)
