drm/amd/display: fix dcn1 dppclk when min dispclk patch applies

Applying min dispclk patch would result in incorrect dppclk divider
without this change

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>