Fix parameter name in Doxygen documentation
diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index 90f5b64..8988be1 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -574,11 +574,12 @@
  *
  * For example, `PSA_ALG_HMAC(PSA_ALG_SHA256)` is HMAC-SHA-256.
  *
- * \param alg   A hash algorithm (\c PSA_ALG_XXX value such that
- *              #PSA_ALG_IS_HASH(alg) is true).
+ * \param hash_alg      A hash algorithm (\c PSA_ALG_XXX value such that
+ *                      #PSA_ALG_IS_HASH(alg) is true).
  *
- * \return      The corresponding HMAC algorithm.
- * \return      Unspecified if \p alg is not a hash algorithm.
+ * \return              The corresponding HMAC algorithm.
+ * \return              Unspecified if \p alg is not a supported
+ *                      hash algorithm.
  */
 #define PSA_ALG_HMAC(hash_alg)                                  \
     (PSA_ALG_HMAC_BASE | ((hash_alg) & PSA_ALG_HASH_MASK))