drm/amd/display: Fix incorrect dsc force enable logic

[Why]
Missed removing a '!' which results in incorrect behavior

[How]
Remove the offending '!'
Signed-off-by: Eryk Brol <eryk.brol@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201015194053.355335-1-eryk.brol@amd.com

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c

@@ -647,7 +647,7 @@ static void try_disable_dsc(struct drm_atomic_state *state,
 	for (i = 0; i < count; i++) {
 		if (vars[i].dsc_enabled
 				&& vars[i].bpp_x16 == params[i].bw_range.max_target_bpp_x16
-				&& !params[i].clock_force_enable == DSC_CLK_FORCE_DEFAULT) {
+				&& params[i].clock_force_enable == DSC_CLK_FORCE_DEFAULT) {
 			kbps_increase[i] = params[i].bw_range.stream_kbps - params[i].bw_range.max_kbps;
 			tried[i] = false;
 			remaining_to_try += 1;