MDEV-20500: Bad error msg on disabling local infile

mysql-test/suite/sys_vars/r/local_infile_func.result

@@ -29,7 +29,7 @@ DROP TABLE IF EXISTS t1;
 create table t1(a int);
 LOAD DATA LOCAL INFILE
 'MYSQLTEST_VARDIR/std_data/numbers.txt' INTO TABLE test.t1;
-ERROR 42000: The used command is not allowed with this MariaDB version
+ERROR HY000: The used command is not allowed because the MariaDB server or client has disabled the local infile capability
 SELECT count(*) from t1;
 count(*)
 0

mysql-test/suite/sys_vars/t/local_infile_func.test

@@ -74,7 +74,7 @@ DROP TABLE IF EXISTS t1;
 create table t1(a int);
 
 --replace_result $MYSQLTEST_VARDIR MYSQLTEST_VARDIR
---Error ER_NOT_ALLOWED_COMMAND
+--Error ER_LOAD_INFILE_CAPABILITY_DISABLED
 eval LOAD DATA LOCAL INFILE
 '$MYSQLTEST_VARDIR/std_data/numbers.txt' INTO TABLE test.t1;
 

sql/share/errmsg-utf8.txt

@@ -7944,4 +7944,7 @@ ER_WARN_HISTORY_ROW_START_TIME
 ER_PART_STARTS_BEYOND_INTERVAL
         eng "%`s: STARTS is later than query time, first history partition may exceed INTERVAL value"
 ER_GALERA_REPLICATION_NOT_SUPPORTED
-	eng "DDL-statement is forbidden as table storage engine does not support Galera replication"
+        eng "DDL-statement is forbidden as table storage engine does not support Galera replication"
+ER_LOAD_INFILE_CAPABILITY_DISABLED
+        eng "The used command is not allowed because the MariaDB server or client has disabled the local infile capability"
+        rum "Comanda folosită nu este permisă deoarece clientul sau serverul MariaDB a dezactivat această capabilitate"

sql/sql_parse.cc

@@ -4940,8 +4940,9 @@ mysql_execute_command(THD *thd)
       if (!(thd->client_capabilities & CLIENT_LOCAL_FILES) ||
           !opt_local_infile)
       {
-	my_message(ER_NOT_ALLOWED_COMMAND, ER_THD(thd, ER_NOT_ALLOWED_COMMAND), MYF(0));
-	goto error;
+        my_message(ER_LOAD_INFILE_CAPABILITY_DISABLED, 
+                   ER_THD(thd, ER_LOAD_INFILE_CAPABILITY_DISABLED), MYF(0));
+        goto error;
       }
     }