docs: kernel_include.py: remove range restriction for gen docs

docs: kernel_include.py: remove range restriction for gen docs

Originally, parse-readers were generating an output where
the first two lines were setting a literal block.

The script now gets only the actual parsed data without that,
so it is now safe to allow start-line and end-line parameters
to be handled.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/5dff693860a6a3faade15c24abdc380f09db468d.1755872208.git.mchehab+huawei@kernel.org