net/activemq: Fix rc script stop command

The stop command fails because it cannot connect to activemq, so
the rc script currently always kills activemq which might lead to
lost data, database corruption, left-over lock files, etc. Run the
stop command under the activemq user too like the jps command in
activemq_check_pidfile() so that it can actually shutdown activemq.

• While here fix log files location

PR: 207881
Reported by: bwilliamson@bex.net