Drop "rocko" and "sumo" from LAYERSERIES_COMPAT.
Drop "rocko" and "sumo" from LAYERSERIES_COMPAT.

Firefox had not been working with those branches due to the lack of a
compatible nodejs-native version; now that we require clang for Chromium and
the version available for those branches is too old, officially retire
support for those branches from `conf/layer.conf`.

Signed-off-by: Raphael Kubo da Costa <5fe4d20cf6ab8a2cf4e5e71d4c2d58346e96df0d@intel.com>

webdino/meta-browser,OSSystems/meta-browser,webdino/meta-browser,OSSystems/meta-browser,webdino/meta-browser,webdino/meta-browser,OSSystems/meta-browser,schnitzeltony/meta-browser,schnitzeltony/meta-browser,OSSystems/meta-browser,schnitzeltony/meta-browser,schnitzeltony/meta-browser,webdino/meta-browser