Issue 49122 - Filtered nsrole that uses nsrole crashes the
Bug Description: When evaluating a filter role that uses "nsrole" in the filter
crashes the server due infinite loop that leads to a stack
Fix Description: Virtual attributes are not allowed to be used in role filters.
We were already checking for COS attributes, but not nsrole.
Also did some minor code cleanup
Reviewed by: nhosoi(Thanks!)
(cherry picked from commit a95889def41d3869692d7259a9213b1f9238f3c8)
(cherry picked from commit d589950cdd8ac9a0756b67cfe4ae3a33da094065)