pinctrl: renesas: rzg2l: Use devm_clk_get_enabled() helper

The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the need of a dedicated function used
with devm_add_action_or_reset().

While at it, use dev_err_probe() which filters -EPROBE_DEFER.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/a4a586337d692f0ca396b80d275ba634eb419593.1690058500.git.christophe.jaillet@wanadoo.fr


[geert: Make clk local to rzg2l_pinctrl_probe()]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>