clk: imx: imx6ul: fix default parent for enet*_ref_sel

clk: imx: imx6ul: fix default parent for enet*_ref_sel

The clk_set_parent for "enet1_ref_sel" and  "enet2_ref_sel" are
incorrect, therefore the original requirements to have "enet_clk_ref" as
output sourced by iMX ENET PLL as a default config is not met.

Only "enet[1,2]_ref_125m" "enet[1,2]_ref_pad" are possible parents for
"enet1_ref_sel" and "enet2_ref_sel".

This was observed as a regression using a custom device tree which was
expecting this default config.

This can be fixed at the device tree level but having a default config
matching the original behavior (before refclock mux) will avoid breaking
existing configs.

Fixes: 4e197ee880c2 ("clk: imx6ul: add ethernet refclock mux support")
Link: https://lore.kernel.org/lkml/20230306020226.GC143566@dragon/T/
Signed-off-by: Sebastien Laveze <slaveze@smartandconnective.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20240528151434.227602-1-slaveze@smartandconnective.com
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>