In commit 176d2cda we added the @die-id field
to the CpuInstanceProperties struct, but in the process
accidentally removed the newline between the doc-comment
lines for @core-id and @thread-id.

Put the newline back in; this fixes a misformatting in the
generated HTML QMP reference manual.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200729191019.19168-1-peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>