drm/amdgpu/cz: fix cz_dpm_update_low_memory_pstate logic

The logic was reversed.  This feature is not enabled
at the moment, but fix it now for the future.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/cz_dpm.c

@@ -1596,9 +1596,9 @@ static int cz_dpm_update_low_memory_pstate(struct amdgpu_device *adev)
 
 	if (pi->sys_info.nb_dpm_enable) {
 		if (ps->force_high)
-			cz_dpm_nbdpm_lm_pstate_enable(adev, true);
-		else
 			cz_dpm_nbdpm_lm_pstate_enable(adev, false);
+		else
+			cz_dpm_nbdpm_lm_pstate_enable(adev, true);
 	}
 
 	return ret;