drm/amd/display: add dc interface for query QoS information

drm/amd/display: add dc interface for query QoS information

[why]
Add support for retrieving Quality of Service (QoS) metrics from dc
to enable performance analysis and bottleneck identification. This provides
benchmark tools with real-time bandwidth and latency measurements from hardware
performance counters, helping diagnose display system performance issues.

[how]
- Add dc_get_qos_info() function to DC layer for unified QoS data retrieval
- Implement hardware sequencer interface with function pointers for QoS
measurements
- Integrate QoS metrics: peak/average bandwidth (Mbps) and max/average
latency (ns)

Reviewed-by: Aric Cyr <aric.cyr@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>