pinctrl: rockchip: improve error message for incorrect rockchip,pins property

If one improperly writes a rockchip,pins property, the pinctrl driver
basically just states that one in the myriad of pinctrl nodes is
improper but does not tell you which one.

Instead, let's print the full name of the Device Tree node that is
improper as well as provide more context on what the expected content
is.

Note that this should be rather unnecessary if one reads the output of
the dtbs_check as it would be highlighted as an error.

Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/20241002-pinctrl-rockchip-error-modulo-4-v1-1-4addb4e5732a@cherry.de


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>