Don't send error 0 to my_printf_error()

Fixed by adding HA_ERR_INFO as a informational warning to by used by MyISAM
This is used to inform when we create a backup copy of the data file.

Also improved informational messages when creating backup copies of data and index files

include/my_base.h

@@ -503,7 +503,8 @@ enum ha_base_keytype {
 #define HA_ERR_FTS_TOO_MANY_WORDS_IN_PHRASE 191 /* Too many words in a phrase */
 #define HA_ERR_DECRYPTION_FAILED  192 /* Table encrypted but
 						decypt failed */
-#define HA_ERR_LAST               192    /* Copy of last error nr */
+#define HA_ERR_INFO		  193    /* Information, not critical */
+#define HA_ERR_LAST               193    /* Copy of last error nr */
 
 /* Number of different errors */
 #define HA_ERR_ERRORS            (HA_ERR_LAST - HA_ERR_FIRST + 1)

include/my_handler_errors.h

@@ -95,7 +95,8 @@ static const char *handler_error_messages[]=
   "Disk full",
   "Incompatible key or row definition between the MariaDB .frm file and the information in the storage engine. You have to dump and restore the table to fix this",
   "Too many words in a FTS phrase or proximity search",
-  "Table encrypted but decryption failed. This could be because correct encryption management plugin is not loaded, used encryption key is not available or encryption method does not match."
+  "Table encrypted but decryption failed. This could be because correct encryption management plugin is not loaded, used encryption key is not available or encryption method does not match.",
+  "Information, not an error"
 };
 
 #endif /* MYSYS_MY_HANDLER_ERRORS_INCLUDED */

storage/myisam/ha_myisam.cc

@@ -1669,8 +1669,8 @@ bool ha_myisam::check_and_repair(THD *thd)
     {
       char buff[MY_BACKUP_NAME_EXTRA_LENGTH+1];
       my_create_backup_name(buff, "", check_opt.start_time);
-      sql_print_information("Making backup of index file with extension '%s'",
-                            buff);
+      sql_print_information("Making backup of index file %s with extension '%s'",
+                            file->s->index_file_name, buff);
       mi_make_backup_of_index(file, check_opt.start_time,
                               MYF(MY_WME | ME_JUST_WARNING));
     }

storage/myisam/mi_check.c

@@ -4767,9 +4767,10 @@ static int replace_data_file(HA_CHECK *param, MI_INFO *info,
   {
     char buff[MY_BACKUP_NAME_EXTRA_LENGTH+1];
     my_create_backup_name(buff, "", param->backup_time);
-    my_printf_error(0,                          /* No error, just info */
-                    "Making backup of data file with extension '%s'",
-                    MYF(ME_JUST_INFO | ME_NOREFRESH), buff);
+    my_printf_error(HA_ERR_INFO,             /* No error, just info */
+                    "Making backup of data file %s with extension '%s'",
+                    MYF(ME_JUST_INFO | ME_NOREFRESH), share->data_file_name,
+                    buff);
   }
 
   /*