ofp-actions: Avoid buffer overread in BUNDLE action decoding.

Reported-at: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9052
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
parse_SET_FIELD(const char *arg, struct ofpbuf *ofpacts,
                enum ofputil_protocol *usable_protocols)
{
    char *copy = xstrdup(arg);
    char *error = set_field_parse__(copy, ofpacts, usable_protocols);
    free(copy);
    return error;
}

parse_SET_FIELD(const char *arg, struct ofpbuf *ofpacts,
                enum ofputil_protocol *usable_protocols)
{
    char *copy = xstrdup(arg);
    char *error = set_field_parse__(copy, ofpacts, usable_protocols);
    free(copy);
    return error;
}
