Revert "drm/amd/display: Reset freesync config before update new state"

This change caused PSR SU panels to not read from their remote fb,
preventing us from entering self-refresh. It is a regression.

This reverts commit 6b8487cd.

Signed-off-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>