sched: update queue stats read for config flexibility

sched: update queue stats read for config flexibility

Modify pipe queue stats read function to allow different subports
of the same port to have different configuration in terms of number
of pipes, pipe queue sizes, etc.

Signed-off-by: Jasvinder Singh <jasvinder.singh@intel.com>
Signed-off-by: Lukasz Krakowiak <lukaszx.krakowiak@intel.com>