misc: move the RDT interface to common library

The current RDT class and interface was define by the clos.py which is
mix get and merge RDT policy, create clos nodes.

Now we need call these interface to check the CLOS IDs number after
merged RDT policy, so this patch abstract the RDT interface to common
and add an assert to check the CLOS IDs number.

Tracked-On: #6690
Signed-off-by: Chenli Wei <chenli.wei@intel.com>
Signed-off-by: Junjie Mao <junjie.mao@intel.com>

misc/config_tools/scenario_config/elementpath_overlay.py

@@ -9,6 +9,7 @@
 from decimal import Decimal
 from copy import copy
 import operator
+import rdt
 import elementpath
 
 BaseParser = elementpath.XPath2Parser
@@ -20,6 +21,8 @@ class CustomParser(BaseParser):
 
         'has',
         'duplicate-values',
+
+        'number-of-clos-id-needed',
         }
 
 method = CustomParser.method
@@ -84,6 +87,14 @@ def select_duplicate_values_function(self, context=None):
 
     yield from duplicate_values()
 
+@method(function('number-of-clos-id-needed', nargs=1))
+def evaluate_number_of_clos_id_needed(self, context=None):
+    op = self.get_argument(context, index=0)
+    try:
+        return len(rdt.get_policy_list(op.elem)) if op else 0
+    except AttributeError as err:
+        raise self.error('XPTY0004', err)
+
 ###
 # Collection of counter examples