migration-guides: preliminary description for 3.5

(From yocto-docs rev: 2c24dd801b8d9fa4b81726dcde34a69fde309e4a)

Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/migration-guides/migration-3.5.rst

@@ -104,10 +104,17 @@ Recipe changes
 - :ref:`allarch <ref-classes-allarch>` packagegroups can no longer depend on packages
   which use :term:`PKG` renaming such as :ref:`ref-classes-debian`.
 
+- :term:`LICENSE` definitions now have to use `SPDX identifiers <https://spdx.org/licenses/>`__.
+  A :oe_git:`convert-spdx-licenses.py </openembedded-core/tree/scripts/contrib/convert-spdx-licenses.py>`
+  script can be used to update your recipes.
+
+- :term:`SRC_URI`: a new :ref:`bitbake:bitbake-user-manual/bitbake-user-manual-fetching:crate fetcher (\`\`crate://\`\`)`
+  is available for Rust packages.
+
 Class changes
 -------------
 
-- The `distutils*.bbclasses` have been moved to `meta-python`. The classes and
+- The ``distutils*.bbclasses`` have been moved to ``meta-python``. The classes and
   `DISTUTILS*` variables have been removed from the documentation.
 
 - ``blacklist.bbclass`` is removed and the functionality moved to the
@@ -116,3 +123,48 @@ Class changes
   function. The usage will remain the same::
 
      SKIP_RECIPE[my-recipe] = "Reason for skipping recipe"
+
+- The Python package build process based on `wheels <https://pythonwheels.com/>`__.
+  Here are the new Python packaging classes that should be used:
+  :ref:`python-flit_core <ref-classes-python_flit_core>`,
+  :ref:`setuptools_python-build_meta <ref-classes-python_setuptools_build_meta>`
+  and :ref:`python_poetry_core <ref-classes-python_poetry_core>`.
+
+- ``image-prelink.bbclass`` class is removed.
+
+- New :ref:`overlayfs <ref-classes-overlayfs>` and
+  :ref:`overlayfs-etc <ref-classes-overlayfs-etc>` classes are available
+  to make it easier to overlay read-only filesystems (for example)
+  with `OverlayFS <https://en.wikipedia.org/wiki/OverlayFS>`__.
+
+Configuration changes
+---------------------
+
+- The Yocto Project now allows to reuse Shared State from its autobuilder.
+  If the network connection between our server and your machine is faster
+  than you would build recipes, you can try to speed up your builds
+  by using such Share State and Hash Equivalence by setting::
+
+     BB_SIGNATURE_HANDLER = "OEEquivHash"
+     BB_HASHSERVE = "auto"
+     BB_HASHSERVE_UPSTREAM = "typhoon.yocto.io:8687"
+     SSTATE_MIRRORS ?= "file://.* https://sstate.yoctoproject.org/&YOCTO_DOC_VERSION;/PATH;downloadfilename=PATH"
+
+Supported host distribution changes
+-----------------------------------
+
+- New support for `AlmaLinux <https://en.wikipedia.org/wiki/AlmaLinux>`__
+  hosts replacing `CentOS <https://en.wikipedia.org/wiki/CentOS>`__.
+  The following distribution versions were dropped: CentOS 8, Ubuntu 16.04 and Fedora 30, 31 and 32.
+
+Changes for release notes
+-------------------------
+
+- Share State cache: now using `ZStandard (zstd) <https://en.wikipedia.org/wiki/Zstd>`__
+  instead of Gzip compression, for better performance.
+
+- BitBake has an improved ``setscene`` task display.
+
+- This release fixes the reproducibility issues with ``rust-llvm`` and ``golang``.
+  Recipes in OpenEmbedded-Core are now fully reproducible.
+