clk: imx: imx8ulp: Fix XBAR_DIVBUS and AD_SLOW clock parents

clk: imx: imx8ulp: Fix XBAR_DIVBUS and AD_SLOW clock parents

XBAR_DIVBUS and AD_SLOW should set parent to XBAR_AD_DIVPLAT and
XBAR_DIVBUS respectively, not the NIC_AD. otherwise we will get
wrong clock rate.

Fixes: c43a801a5789 ("clk: imx: Add clock driver for imx8ulp")
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230331063814.2462059-2-peng.fan@oss.nxp.com
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>