Do some fixes at groups() description for it to be parsed by Sphinx and add it to the documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <799178cf30dd4022fdb1d029ba998a458e037b52.1773823995.git.mchehab+huawei@kernel.org>