In some instances, the GPU is transmitting repeated frame to the sink
without any updates or changes in the content. These repeat transmission
are wasteful, resulting in power draw in different aspects of the system

1. DCN is fetching the frame of data from DF/UMC/DRAM. This memory traffic
prevents power down of parts of this HW path.

2. GPU is transmitting pixel data to the display through the main link of
the DisplayPort interface. This prevents power down of both the Source
transmitter (TX) and the Sink receiver (RX)

The concepts of utilizing replay is similar to PSR, but there is a benefit of:
	Source and Sink remaining synchronized which allows for
        	- lower latency when switching from replay to live frames
	        - enable the possibility of more use cases
		- easy control of the sink's refresh rate during replay

Due to Source and Sink remaining timing synchronized, Replay can be activated
in more UI scenarios.
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>