clk: rockchip: rk3036: enable the CLK_IGNORE_UNUSED flag for hclk_vio_bus

HCLK_VIO_BUS is the noc bus controller clock for display module,
due to it shouldn't belong to any driver, but we need it enabled,
so just mark it as the CLK_IGNORE_UNUSED flag.

Signed-off-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>