[oe] New layout for OpenEmbedded layers

[Marcin Juszkiewicz]

Hello

Now at Linaro we have two layers for our OpenEmbedded work:

- meta-aarch64
- meta-linaro

First one contains everything we need to get AArch64 booted in
fastmodels: toolchain, kernel and few recipes which needed changes to
build for AArch64. I am working on merging those changes into main
OpenEmbedded layers.

Second one is gcc-linaro from Toolchain WG and some recipes and changes
from Platform team.

Those who do OE builds with our toolchain have some components changed
due to our metadata (like Busybox with dpkg-deb) and I decided to fix it.

Today I pushed "new-layout" branch of meta-linaro repository. It
contains all Linaro layers:

- meta-aarch64
- meta-linaro
- meta-linaro-toolchain

First one was merged from meta-aarch64 repository and moved to own
directory. Third one contains only toolchain bits. Second one has all
that left.

I have to do some test builds with this layout and once they will
confirm that it works I will change all CI builds. This will also
deprecate meta-aarch64 repository - it will not have any updates and
will be dropped in ~month.

Opinions?