[WFCORE-444] Use JAVA_OPTS environment variable for process controllet and host controller on Windows

JIRA: https://issues.jboss.org/browse/WFCORE-444

The `JAVA_OPTS` environment variable was not propagated properly in `domain.conf.bat` so the process controller and host controller were running without correct java arguments set.

This fix aligns the behavior with the `standalone.conf.bat` (and also Unix/Linux `*.conf` scripts)