drm/amd/display: Disable PSR-SU on eDP panels

[Why]
PSR-SU may cause some glitching randomly on several panels.

[How]
Temporarily disable the PSR-SU and fallback to PSR1 for
all eDP panels.

Link: drm/amd#3388


Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Sun peng Li <sunpeng.li@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 6deeefb8)
Cc: stable@vger.kernel.org