doc: patch-id: fix accidental literal blocks

doc: patch-id: fix accidental literal blocks

All the final paragraphs on these three options are rendered as
literal blocks. The intent was surely to keep each of them wed to their
respective description list items. But the attempt at maintaining the
indentation level of the block causes each them to be interpreted as a
code block, since code blocks can be represented using indentation.

We need to use list continuation (+) in order to keep them wed to
their blocks.

There is also an unordered list which sandwiches two paragraphs on an
option. We don’t need to do anything about that since it attaches to the
description list item without list continuation (i.e. it is already
correct). But for consistency let’s use list continuation and an open
block on it.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>