What's u-boot-imx?

It's definitely not in openembedded-core, so there's no reason to cross-post
there.

If google doesn't help, it's recommended to post such specific questions to
the corresponding mailing list for the layer this recipe comes from.

If it's not clear where the recipe comes from, Layer Index can help:
https://layers.openembedded.org/

Thanks.

--
Denys