avoid too much FAILED for IS_MYSQLMUNIN

evocheck.sh

@@ -678,6 +678,7 @@ if [ -e /etc/debian_version ]; then
         if is_debianversion stretch && is_installed mariadb-server; then
             for file in mysql_bytes mysql_queries mysql_slowqueries mysql_threads mysql_connections mysql_files_tables mysql_innodb_bpool mysql_innodb_bpool_act mysql_innodb_io mysql_innodb_log mysql_innodb_rows mysql_innodb_semaphores mysql_myisam_indexes mysql_qcache mysql_qcache_mem mysql_sorts mysql_tmp_tables; do
                 test -L /etc/munin/plugins/$file || echo 'IS_MYSQLMUNIN FAILED!'
+                test -L /etc/munin/plugins/$file || break
             done
         fi
     fi