Ansible request for Lcov installation for Code Coverage Report

To enable Code Coverage Report for openj9 (this [issue](https://github.com/eclipse-openj9/openj9/issues/12133)), [Lcov](http://ltp.sourceforge.net/coverage/lcov.php) needs to be installed on x/p/z linux Jenkins machines.

Helpful links:
- https://github.com/eclipse-openj9/openj9/issues/12133
- http://ltp.sourceforge.net/coverage/lcov.php
- ibm_github//runtimes/infrastructure/issues/5763

Thanks.

Start by reviewing the linked OpenJ9 issue 12133 and the Lcov documentation to understand the required coverage report setup. Then locate the Ansible configuration for the x/p/z Linux Jenkins machines and install Lcov there; done means those machines have Lcov available for the OpenJ9 coverage report.

Written by the indexing model from the issue text.