Simplify the code and make path a property of the container (via
intelRdtManager).

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>

Handle ClosID parameter of IntelRdt. Makes it possible to use
pre-configured classes/ClosIDs and avoid running out of available IDs
which easily happens with per-container classes.

Remove validator checks for empty L3CacheSchema and MemBwSchema fields
in order to be able to leave them empty, and only specify ClosID for
a pre-configured class.

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>

Check that the ClosID directory pre-exists if no L3 or MB schema has
been specified. Conform with the following line from runtime-spec
(config-linux):

  If closID is set, and neither of l3CacheSchema and memBwSchema are
  set, runtime MUST check if corresponding pre-configured directory
  closID is present in mounted resctrl. If such pre-configured directory
  closID exists, runtime MUST assign container to this closID and
  generate an error if directory does not exist.

Add a TODO note for verifying existing schemata against L3/MB
parameters.

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>

Run unit tests irrespective of the underlying system configuration, i.e.
even if RDT has not been enabled or is not supported. The tests do not
depend on real kernel interfaces.

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>

Use the term "clos group" instead of "container_id group" as the group
that a container belongs to is not necessarily tied to its container id.

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>