Patch created mechanically by rerunning:

  $  spatch --sp-file scripts/coccinelle/error_propagate_null.cocci \
            --macro-file scripts/cocci-macro-file.h \
            --dir . --in-place

Whitespace tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181213173113.11211-1-armbru@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>