drm/amd/display: Attach VRR properties for eDP connectors

[Why]
eDP was missing in the checks for supported VRR connectors.

[How]
Attach the properties for eDP connectors too.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202449
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>