Match spacing in pointer types in documentation with the code style

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 866f7e3..362e921 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -245,9 +245,9 @@
  */
 /* This is a deprecated variant of `struct psa_custom_key_parameters_s`.
  * It has exactly the same layout, plus an extra field which is a flexible
- * array member. Thus a `const struct psa_key_production_parameters_s*`
+ * array member. Thus a `const struct psa_key_production_parameters_s *`
  * can be passed to any function that reads a
- * `const struct psa_custom_key_parameters_s*`.
+ * `const struct psa_custom_key_parameters_s *`.
  */
 struct psa_key_production_parameters_s {
     uint32_t flags;