docs: kdoc_re: handle strings and escape chars on NextMatch

docs: kdoc_re: handle strings and escape chars on NextMatch

The logic inside NestedMatch currently doesn't consider that
function arguments may have chars and strings, which may
eventually contain delimiters.

Add logic to handle strings and escape characters on them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <ac25335bc2d09649e17d1c86c17d3f8f2e8ec27c.1772469446.git.mchehab+huawei@kernel.org>