clk: rockchip: rk3588: Fix clk_aux16m in clock driver

The rate and error value is not returned for aux16m clocks, fix this.

Fixes: 7a474df7 ("clk: rockchip: Add rk3588 clk support")
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>