usb: xhci-mtk: update fs bus bandwidth by bw_budget_table

Use @bw_budget_table[] to update fs bus bandwidth due to
not all microframes consume @bw_cost_per_microframe, see
setup_sch_info().

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1629189389-18779-6-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>