Fix sparse warning:
drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_resource.c:963:6:
 warning: symbol 'calculate_integer_scaling' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
        return false;
 }
 
-void calculate_integer_scaling(struct pipe_ctx *pipe_ctx)
+static void calculate_integer_scaling(struct pipe_ctx *pipe_ctx)
 {
        if (!pipe_ctx->plane_state->scaling_quality.integer_scaling)
                return;