[U-Boot] [U-Boot, 1/4] pinctrl: exit pinconfig_post_bind if there are no subnodes

[Philipp Tomsich]

> This fixes RK3288 SPL hanging or hitting this assert:
> drivers/core/ofnode.c:183: ofnode_first_subnode: Assertion `ofnode_valid(node)' failed.
> 
> Signed-off-by: Urja Rannikko <urjaman at gmail.com>
> Reviewed-by: Simon Glass <sjg at chromium.org>
> ---
>  drivers/pinctrl/pinctrl-uclass.c | 3 +++
>  1 file changed, 3 insertions(+)
> 

Reviewed-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>