drm/amd/display: Fix HW/SW state mismatch

[Why]
When we disable a connector we don't explicitly remove it from the module so the
display is still cached(SW) in the hdcp_module.

SST: no issues because we can only have 1 display per link

MST: We have x displays per link, now if we disable 1 we don't remove it from the
module so the module has x display cached(SW).

If we try to enable HDCP, psp verification will fail because we are reporting x
displays while the HW only has x-1 display enabled

[How]
Check the callback for when we disable stream and call remove display.

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>