Startup success detection mechanism fails if JBOSS_HOME and jboss.server.base.dir are set differently.

If the property `jboss.server.base.dir` and the environment variable `JBOSS_HOME` point to different directories (which we do, for instance, to start multiple JBoss/Wildfly instances, each with its own standalone directory) then the startup success detection mechanism implemented by the script <WILDFLY_HOME>/bin/init.d/wildfly-init-debian.sh wrongly reports startup as failed even if it actually succeeded.

Tracing it down, I found that since Wildly 10 the startup script searches for the file `<JBOSS_HOME>/standalone/tmp/startup-marker`. However, that file is actually written to `jboss.server.base.dir/tmp/startup-marker`; hence, it is not found if the directories are not the same.

I don't see a way how to fix this. As far as I can seen, it's not possible to access the jboss.server.base.dir property within the startup script. But the use case of having separate directories should be supported and it should work.