patch 7.4.979

Problem:    When changing the crypt key the blocks read from disk are not
            decrypted.
Solution:   Also call ml_decrypt_data() when mf_old_key is set. (Ken Takata)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    979,
 /**/
     978,
 /**/