Add PSA_ERROR_BUFFER_TOO_SMALL to psa_mac_compute
diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index 6259a97..8a1e262 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -1243,6 +1243,8 @@
  *         \p handle is not compatible with \p alg.
  * \retval #PSA_ERROR_NOT_SUPPORTED
  *         \p alg is not supported or is not a MAC algorithm.
+ * \retval #PSA_ERROR_BUFFER_TOO_SMALL
+ *         \p mac_size is too small
  * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
  * \retval #PSA_ERROR_COMMUNICATION_FAILURE
  * \retval #PSA_ERROR_HARDWARE_FAILURE