Revert "drm/amd/display: Enable Freesync Video Mode by default"

This reverts commit de05abe6.

The bug referenced below was bisected to this commit. There has been no
activity toward fixing it in 3 months, so let's revert for now.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/2162


Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org