drm/amd/display: Remove redundant hdcp display state

[Why]
Due to previous code changes displays which are in active state
immediately transition to the active and added state. This makes the two
states redundant and unnecessary.

[How]
Instead of updating the device state to active and added after
successful addition, change state to inactive if addition failed. Also,
change references to active and added state to just added state.

Signed-off-by: Isabel Zhang <isabel.zhang@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>