logrt[]: warning "there are no files matching "....." in "....."" can be misleading

Steps to reproduce:

1. Create logrt[] item, e.g. logrt[/home/zabbix/test.log]
2. Append test record, e,g. echo ABC >> /home/zabbix/test.log
3. Observe that test record is reported to server.
4. Append a new test record to a new file, e.g. echo 123 >> /home/zabbix/test.log1
5. Observe that test record is reported to server.
6. Delete the new log file /home/zabbix/test.log1.
7. In agent log file a warning is logged "there are no files matching "test.log" in "/home/zabbix/".

This is confusing for user because there is a log file test.log, which matches the regexp, it is just skipped as already processed.

Proposed solution: modify warning message to look like

there are no recently modified files matching "test.log" in "/home/zabbix/"