docs: ABI: don't escape ReST-incompatible chars from obsolete and removed

With just a single fix, the contents there can be parsed properly
without the need to escape any ReST incompatible stuff.

Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/472f4574b6aa2ff4de5a819db1a4a5c9a34f5168.1604042072.git.mchehab+huawei@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>