[yocto] BSP guide: better example for recursive layer structure than meta-intel?

[Trevor Woerner]

Having a repository-of-layers isn't something that is BSP-only, any
layer can be setup in this way. Maybe this explanation should be cut
from the BSP Guide and moved to a more general manual, say reference?
Or maybe removed altogether? I'm not really sure what it adds; how
repositories are stored and organized inside a revision system (or
otherwise) is inconsequential, so long as bblayers.conf is setup
correctly.

The only repository-of-layers of which I'm aware is meta-linaro
(which, I don't think, is strictly a BSP layer).

If I could go back in time, I'd nix the whole "let's prefix every
layer name with 'meta-'". If every layer is 'meta-', the label itself
becomes useless. It would have been much better if every layer were
prefixed with something useful, such as its type (bsp-intel,
distro-arago, sw-browser). That would be meaningful. Then we could
reserve 'meta-' for the cases where we had repositories-of-layers ;-)