Why:
When resume from sleep or hiberation, blocked MST Topology discovery might
need to be used.

How:
Added "DETECT_REASON_RESUMEFROMS3S4" to enum dc_detect_reason; use it to
require blocked MST Topology discovery.
Reviewed-by: NWenjing Liu <Wenjing.Liu@amd.com>
Acked-by: NJasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: NBing Guo <Bing.Guo@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>