tools/hotplug: move XENSTORED_MOUNT_CTX to sysconfig.xencommons

On a non-SELinux system the mount option "context=none" works fine. But
with SELinux enabled a proper value has to be defined. To simplify the
required adjustment move XENSTORED_MOUNT_CTX from the service file to
the sysconfig file.

There is no need to require the creation of a new sysconfig file, just
reuse the existing /etc/sysconfig/xencommons file.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
tools/hotplug: use existing sysconfig file for xenconsoled

There is no need to require the creation of a new sysconfig file to
pass options to xenconsoled in the systemd service file. Reuse the
existing xencommons file. This file already contains the variable
XENCONSOLED_TRACE, which is used in the sysv runlevel script.

- Adjust systemd service file to use XENCONSOLED_TRACE instead of
  XENCONSOLED_LOG
- Move XENCONSOLED_ARGS and XENCONSOLED_LOG_DIR to the sysconfig file.
- Enable XENCONSOLED_TRACE and set its value to "none" to have a value
  for --log in the service file.
- Adjust the runlevel script to recognize also XENCONSOLED_ARGS and
  XENCONSOLED_LOG_DIR
- Adjust the runlevel script to handle XENCONSOLED_TRACE properly. If
  an old sysconfig file exist the XENCONSOLED_TRACE will remain empty.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
tools/hotplug: remove EnvironmentFile from xen-qemu-dom0-disk-backend.service

The references Environment file does not exist, and the service file
does not make use of variables anyway.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
tools/hotplug: remove XENSTORED_ROOTDIR from service file

There is no need to export XENSTORED_ROOTDIR. This variable can be
enabled in sysconfig/xencommons. If the variable is unset xenstored
will automatically use @XEN_LIB_STORED@.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
tools/hotplug: support XENSTORED_TRACE in systemd

The sysv runlevel script handles the boolean variable XENSTORED_TRACE
from sysconfig.xencommons to enable tracing. Recognize this also to
the systemd service file.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>