[why]
If a typeC to HDMI dongle supports YCbCr420 pass through and VSC
colorimetry and pixel encoding formats in the Extended Receiver
Capability, we shall allow VSC SDP to be used.

[How]
The Extended Receiver Capability field shall check the
EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT bit in the
TRAINING_AUX_RD_INTERVAL register.  Removed DPCD rev checking for VSC
SDP.
Signed-off-by: NDerek Lai <Derek.Lai@amd.com>
Reviewed-by: NWenjing Liu <Wenjing.Liu@amd.com>
Acked-by: NRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: NTony Cheng <Tony.Cheng@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>